Build Beta App for Property Buying & Selling Platform ("Silent Sale")

We are developing a beta version of a property marketplace app called Silent Sale, designed to connect buyers, sellers, and hosts without using traditional real estate agents.

This beta app will need to include:

Buyer account creation and login
Seller account creation and login
Host account (to manage inspections) creation and login
Basic property listing page (seller uploads property details and photos)
Buyer property browsing (simple property feed with filters)
Inspection booking (buyer can request to book a private inspection with the seller/host)
Simple chat/messaging feature between buyer and seller
Push notifications (optional for beta if easy)
Notes:

The UI design should be clean, simple, and modern.
We are looking for basic functionality first — not full commercial polish yet.
This is for proof of concept only — speed and affordability are important.
Preferred Platforms:

iOS and Android (cross-platform frameworks like Flutter or React Native are fine)
OR a mobile-friendly web app if that is faster and cheaper.