I'm building a web platform for local item bartering, where users can exchange second-hand goods without using money. The website should be modern, responsive, and user-friendly. Please help me design the full system with the following features:

User Authentication: Users must be able to register and log in using email or Google. Each user has a profile showing their location, rating, and listed items.

Item Posting System: Users can list items they want to barter. They should input item name, description, condition (new, good, worn), images, location, and what kind of item they want in exchange.

Search & Filter System: Allow users to search and filter items by category, condition, keyword, and proximity.

Real-time Chat & Negotiation: Users should be able to chat in real-time to negotiate barter deals. Optional: allow sending barter requests like offers.

Barter Request System: Let users send and receive barter requests with status tracking (Pending, Accepted, Rejected, Completed). A barter history log is required.

User Rating & Review System: After each completed barter, both parties should rate each other and leave a review to prevent scams.

Nearby Map Integration: Use maps to show nearby items available for barter. Items should appear on the map based on the user’s location or filters.

Admin Dashboard: Admin should have the ability to manage users, verify item listings, and ban suspicious users.

Responsive UI & Dark Mode: The website should have a clean, responsive layout with dark mode support for better user experience on mobile and desktop.

Also, posting an item requires a small payment via static QRIS (QR payment). Please suggest how to implement a payment verification system for static QR codes, and how the system can match a payment to a specific user based on unique transaction amounts.