Windows and doors sales sheet base on square meter!! Google Sheets & AppSheet Developer Needed for Quotation, Invoice & Sales Tracking System Description We are looking for an experienced Google Sheets and AppSheet developer to build a professional quotation, invoice, and sales tracking system for our company. The system will be based on Google Sheets + AppSheet and will be used daily by our sales team. The goal is to create a simple but powerful internal system that manages: Customers Quotations Invoices Receipts Sales performance tracking Main Features 1. Customer Database The system must store and organize customer information, including: Customer Name Phone Email Address Project location Notes This will allow us to maintain a complete customer list that we can access anytime. 2. Quotation System Users must be able to create quotations based on price per square meter. Categories will include for example: Aluminum PVC Glass Other materials The system must automatically calculate totals. Every new quotation must automatically generate a unique quotation number. 3. Discount Control The Admin must control the maximum discount each user can give. Example: Salesperson A → max 5% discount Salesperson B → max 10% discount Users cannot exceed the discount percentage set by the Admin. 4. Invoice System Each quotation must be able to generate up to 3 invoices, such as: Deposit invoice (example 50%) Progress invoice (example 30%) Final invoice (example 20%) The percentages must be adjustable. Each invoice must automatically generate a unique invoice number. 5. Receipt System After payment of each invoice, the system must generate a receipt. Typical workflow: Quotation → Invoice 1 → Receipt 1 → Invoice 2 → Receipt 2 → Invoice 3 → Receipt 3 Each receipt must generate a unique receipt number automatically. 6. Project Completion & Feedback When the project is finished, the system must allow us to record: Customer feedback Project notes Completion status All information must remain stored for future reference. 7. Sales Performance Tracking The system must track the performance of each salesperson. We need to see: How many quotations each salesperson created How many quotations were successfully closed Sales value generated There must also be a visual graph/dashboard that shows the performance of each salesperson. 8. Admin Control Panel The Admin must be able to: Set price per square meter for different product categories Manage users Control maximum discount percentage per user View all data View sales statistics Perform data backups 9. Multi-User System The system should support up to 10 users. Each user can see only their own quotations and invoices The Admin can see everything 10. Data Storage All data must be stored in Google Sheets, with a clean and organized structure. 11. Interface The system must be built with AppSheet and be easy to use on: Mobile Tablet Desktop Requirements Strong experience with Google Sheets Strong experience with ability to build a clean and scalable structure Project Goal Build a reliable internal system that allows our company to: manage customers create quotations generate invoices and receipts track sales performance store project feedback