Neighborhood Garage Sale Organizer — Complete Construction Guide Step 1 — Prepare the accounts and workspace What you are going to accomplish You will create the basic accounts and workspace needed to build the application. 1.1 — Create a Lovable account Lovable will be the main tool used to generate and modify the application. Go to [Lovable](https://lovable.dev/?utm_source=chatgpt.com) and create an account. You do not need to write code at this stage. 1.2 — Create a Supabase account Supabase will store the application's data and manage user authentication. Go to [Supabase](https://supabase.com/?utm_source=chatgpt.com) and create an account. 1.3 — Create a GitHub account GitHub will store the application's source code so that the project can be safely connected to deployment later. Go to [GitHub](https://github.com/?utm_source=chatgpt.com) and create an account. 1.4 — Create a Vercel account Vercel will publish the finished application on the internet. Go to [Vercel](https://vercel.com/?utm_source=chatgpt.com) and create an account. Use the same GitHub account when Vercel offers GitHub connection. Result of this step You should have: Lovable account Supabase account GitHub account Vercel account Checkpoint You can log into all four services successfully. --- Step 2 — Create the application project What you are going to accomplish You will create the initial application with its main pages and overall structure. 2.1 — Start a new Lovable project Open Lovable and create a new application. Give it a clear project name such as: Neighborhood Garage Sale Organizer 2.2 — Give Lovable the initial construction instructions Paste this instruction into the project: Build a complete web SaaS application called "Neighborhood Garage Sale Organizer". The application helps users organize neighborhood garage sales. Required functionality: 1. User registration and login. 2. Users can create and manage garage sale listings. 3. Each garage sale can have a title, description, date, start time, end time, location, and status. 4. Users can add, edit, and remove items belonging to a garage sale. 5. Each item must have a name, description, price, quantity, and availability status. 6. Visitors/users can view garage sale listings and their items. 7. Users can reserve available items. 8. Garage sale organizers can see reservations. 9. Users can participate in garage sales. 10. The application must manage participants for each garage sale. 11. Include notifications inside the application for important events such as reservations and participation changes. 12. Include a dashboard where users can manage their garage sales, items, reservations, participants, and notifications. 13. Users must only be able to modify data they are authorized to manage. 14. Create a clean, responsive interface that works on phones, tablets, and computers. Use a simple SaaS structure with: - public garage sale browsing - authentication - user dashboard - garage sale management - item management - reservations - participants - notifications Do not add unrelated features. Prepare the application to use Supabase for authentication and database storage. 2.3 — Let Lovable generate the initial application Wait for the initial version to finish generating. Do not immediately start changing individual screens. First inspect the whole application. Result of this step You should have an initial application containing the main structure for: Home/public area Login and registration Dashboard Garage sales Items Reservations Participants Notifications Checkpoint Open the generated application and confirm that the main pages can be reached without obvious broken screens. --- Step 3 — Create the Supabase project What you are going to accomplish You will create the database and authentication system. 3.1 — Create a new Supabase project Open Supabase and create a new project. Choose a project name such as: neighborhood-garage-sale Create a strong database password and keep it somewhere safe. 3.2 — Wait for the project to finish Supabase needs time to provision the project. When the project is ready, open its dashboard. 3.3 — Connect Lovable to Supabase Return to Lovable and use its Supabase connection/integration functionality. Select the Supabase project you just created. Follow the connection process shown by Lovable. Do not create a second database. Result of this step Lovable and Supabase are connected. Checkpoint The application should recognize the Supabase project, and Lovable should indicate that the backend connection is active. --- Step 4 — Create the application's database structure What you are going to accomplish You will create the database tables required to store users, garage sales, items, reservations, participants, and notifications. Ask Lovable to create the database structure in Supabase with this specification: Create the Supabase database structure for the application. Create these logical tables: profiles - id - full_name - created_at garage_sales - id - organizer_id - title - description - sale_date - start_time - end_time - location - status - created_at - updated_at items - id - garage_sale_id - name - description - price - quantity - availability_status - created_at - updated_at reservations - id - item_id - user_id - quantity - status - created_at - updated_at participants - id - garage_sale_id - user_id - status - created_at notifications - id - user_id - garage_sale_id - type - title - message - read_status - created_at Create appropriate relationships between these tables. A garage sale belongs to one organizer. A garage sale has many items. A garage sale has many participants. An item belongs to one garage sale. A reservation belongs to one item and one user. A notification belongs to one user and may refer to one garage sale. Use the authenticated user's ID for ownership relationships. 4.1 — Check the tables Open the Supabase database table area. Confirm that the required tables exist. 4.2 — Check the relationships Confirm that: Garage sales are connected to their organizers. Items are connected to garage sales. Reservations are connected to items and users. Participants are connected to garage sales and users. Notifications are connected to users. Result of this step The application now has a real database structure instead of temporary interface data. Checkpoint You can see the required tables and their relationships inside Supabase. --- Step 5 — Configure user registration and login What you are going to accomplish Users will be able to create accounts and securely access their dashboards. 5.1 — Configure authentication Use Supabase Authentication. Enable the email/password authentication method. Do not add other authentication methods unless they are required for the application. 5.2 — Connect registration to Supabase Ask Lovable to make registration create a Supabase authentication account and a corresponding profile. Use this instruction: Connect registration and login to Supabase Authentication. When a user registers: 1. Create the authenticated Supabase user. 2. Create the corresponding profile record. 3. Store the user's full name. 4. Redirect the authenticated user to the dashboard. When a user logs in successfully: 1. Restore the authenticated session. 2. Redirect the user to the dashboard. When a user logs out: 1. End the Supabase session. 2. Return the user to the public area. Protect the dashboard so unauthenticated users cannot access it. 5.3 — Test registration Create a test account. Then log out. Log back in with the same account. Result of this step Authentication works. Checkpoint A registered user can: Register → Log in → See dashboard → Log out → Log in again. --- Step 6 — Build garage sale management What you are going to accomplish Users will be able to create and manage their garage sales. 6.1 — Create the garage sale form The form must contain: Title Description Date Start time End time Location Status Keep the form simple. 6.2 — Save garage sales When the user submits the form: 1. Verify that the user is logged in. 2. Save the garage sale in Supabase. 3. Store the authenticated user's ID as the organizer. 4. Return the user to the garage sale management area. 6.3 — Display the user's garage sales The dashboard should show the garage sales created by the current user. Each garage sale should provide actions to: View Edit Delete 6.4 — Protect ownership A user must not be able to edit or delete another user's garage sale. Ask Lovable to enforce this through Supabase security rules as well as the application interface. Result of this step A user can create and manage their own garage sales. Checkpoint Create a test garage sale and verify that it appears in the dashboard and can be edited. --- Step 7 — Build item management What you are going to accomplish Organizers will be able to create the items being offered at each garage sale. 7.1 — Add items to a garage sale Create an item form containing: Item name Description Price Quantity Availability status 7.2 — Save the item When an organizer adds an item: 1. Identify the garage sale. 2. Verify that the current user owns that garage sale. 3. Save the item under that garage sale. 4. Display it in the garage sale's item list. 7.3 — Add item management Allow the organizer to: Add an item Edit an item Remove an item Change its availability status 7.4 — Prevent unauthorized changes A user who does not organize the garage sale must not be able to modify its items. Result of this step Each garage sale can contain a complete list of available items. Checkpoint Create at least three test items and confirm that they appear under the correct garage sale. --- Step 8 — Build public garage sale listings What you are going to accomplish Users can discover garage sales without entering the management dashboard. 8.1 — Create the listing page Display garage sales with basic information: Title Date Time Location Description Organizer 8.2 — Create the detail page When someone opens a garage sale, show: Complete sale information Location Date and time Available items Prices Availability 8.3 — Keep management controls private Only the organizer should see controls for editing or deleting the garage sale. Visitors should see the public information instead. Result of this step Garage sales can be discovered and viewed through the public part of the application. Checkpoint Log out and verify that the public garage sale information remains visible. --- Step 9 — Build reservations What you are going to accomplish Users will be able to reserve available items. 9.1 — Add the reservation action On an available item, provide a clear reservation action. The user chooses the quantity they want to reserve. 9.2 — Validate the reservation Before creating a reservation, verify: The user is authenticated. The item exists. The item is available. The requested quantity is greater than zero. The requested quantity does not exceed the available quantity. 9.3 — Save the reservation Store: User Item Quantity Reservation status Creation date 9.4 — Prevent invalid reservations The application must reject a reservation when the requested quantity is greater than the available quantity. 9.5 — Show the organizer's reservations The garage sale organizer should be able to see reservations associated with their items. 9.6 — Show the user's reservations Users should have an area where they can see the reservations they have made. Result of this step The application now supports item reservations. Checkpoint Create two test accounts. Use one account to create an item. Use the second account to reserve it. Verify that the reservation appears for both the user and the organizer. --- Step 10 — Build participant management What you are going to accomplish Users can participate in garage sales, while organizers can manage participants. 10.1 — Add participation On a garage sale detail page, provide an action allowing an authenticated user to participate. 10.2 — Save the participant Create a participant record containing: Garage sale User Participation status Creation date 10.3 — Prevent duplicate participation A user should not create multiple active participant records for the same garage sale. 10.4 — Show participants to the organizer The organizer dashboard should display the participants for each garage sale. 10.5 — Allow participation status management The organizer should be able to manage the participant's status using the statuses supported by the application. Result of this step Garage sale organizers can see and manage participants. Checkpoint Use a second test account to join a garage sale and verify that the organizer can see that participant. --- Step 11 — Build notifications What you are going to accomplish The application will inform users about important events. To keep the project simple, use in-app notifications rather than introducing another notification service. 11.1 — Create the notification area Add a notifications section to the authenticated user's dashboard. Show: Notification title Message Date Read/unread status 11.2 — Create reservation notifications When a reservation is created, generate an appropriate notification for the garage sale organizer. 11.3 — Create participant notifications When a user joins a garage sale, generate a notification for the organizer. When the organizer changes the participant's status, generate an appropriate notification for that participant. 11.4 — Add read status Allow users to mark notifications as read. Result of this step Users receive important application notifications without requiring another external service. Checkpoint Create a reservation and participation event using test accounts and confirm that the corresponding notifications appear. --- Step 12 — Build the complete dashboard What you are going to accomplish You will bring all management functions together in one clear dashboard. 12.1 — Organizer dashboard The organizer should be able to reach: My garage sales Items Reservations Participants Notifications 12.2 — User dashboard A normal authenticated user should be able to reach: My reservations My participation Notifications 12.3 — Add clear navigation Keep navigation simple and consistent. Do not add unnecessary sections. 12.4 — Display useful empty states If a user has no garage sales, reservations, participants, or notifications, display a clear message rather than an empty screen. Result of this step The main application functions are accessible from a coherent dashboard. Checkpoint Log in with: 1. An organizer account. 2. A normal participant account. Confirm that each sees the appropriate information. --- Step 13 — Add security rules What you are going to accomplish You will prevent users from accessing or modifying data that does not belong to them. 13.1 — Protect profiles Users should only be able to modify their own profile information. 13.2 — Protect garage sales Only the organizer should be able to modify or delete their garage sale. 13.3 — Protect items Only the organizer of the associated garage sale should be able to modify its items. 13.4 — Protect reservations Users should be able to see their own reservations. Organizers should be able to see reservations belonging to their garage-sale items. 13.5 — Protect participants Participants should be able to see their own participation information. Organizers should be able to manage participants belonging to their garage sales. 13.6 — Protect notifications A user must only be able to read and modify their own notifications. 13.7 — Test with two accounts Use two separate accounts and deliberately try to access information belonging to the other account. The application must reject unauthorized actions. Result of this step The application's database has ownership restrictions instead of relying only on hidden interface buttons. Checkpoint Account A cannot modify Account B's garage sale, items, reservations, participants, or notifications. --- Step 14 — Make the application responsive What you are going to accomplish The application will work properly on phones, tablets, and computers. 14.1 — Test the main pages Check: Home Garage sale listings Garage sale details Registration Login Dashboard Garage sale form Item form Reservations Participants Notifications 14.2 — Fix mobile layout problems Ask Lovable to inspect the application at mobile width and correct: Horizontal scrolling Overlapping elements Buttons that are too small Forms that do not fit Tables that are difficult to use Navigation problems 14.3 — Check desktop layout Make sure the same pages remain comfortable to use on a larger screen. Result of this step The application is usable on both mobile and desktop screens. Checkpoint Open the application on a phone-sized screen and verify that the main workflows remain usable. --- Step 15 — Perform a complete functional test What you are going to accomplish You will test the entire application before publishing it. Create two test accounts: Organizer account Participant account 15.1 — Test authentication Verify: Registration Login Logout Protected dashboard 15.2 — Test garage sale creation Using the organizer account: 1. Create a garage sale. 2. Add its date. 3. Add its time. 4. Add its location. 5. Save it. 6. Edit it. 7. Confirm the changes. 15.3 — Test items Add several items. Change an item's quantity and availability. Verify that the changes are saved. 15.4 — Test participation Using the participant account: 1. Open the garage sale. 2. Join it. 3. Return to the dashboard. Confirm that participation is recorded. 15.5 — Test reservations Reserve an available item. Check the reservation from the participant account. Then check it from the organizer account. 15.6 — Test notifications Confirm that the reservation and participation events generate the appropriate in-app notifications. 15.7 — Test security Try to access another user's protected information. The application should reject unauthorized actions. Result of this step The complete core workflow works from beginning to end. Checkpoint You can successfully perform: Register → Create sale → Add items → Participate → Reserve item → Receive notification → Manage participants. --- Step 16 — Save the project in GitHub What you are going to accomplish You will store the application source code in GitHub before deployment. 16.1 — Connect the project to GitHub Use Lovable's GitHub integration if available for the project. Authorize GitHub when requested. 16.2 — Create the repository Create a repository for the application, for example: neighborhood-garage-sale-organizer Keep the repository private unless you specifically need it to be public. 16.3 — Confirm the code is synchronized Open the repository in GitHub. You should see the application's source files. Result of this step Your project has a stored version of its source code. Checkpoint The GitHub repository contains the application code and is connected to the project. --- Step 17 — Deploy the application with Vercel What you are going to accomplish You will publish the application online. 17.1 — Import the GitHub project into Vercel Open Vercel and create a new project from the GitHub repository. Select: neighborhood-garage-sale-organizer 17.2 — Configure the project Vercel should recognize the application's framework. Do not manually change framework settings unless Vercel indicates that something is missing. 17.3 — Add required environment variables If the application uses Supabase envi