Build A Website, admin panel, android app

Hi I want to develop following... 1) Android app for Seller & Buyer 2) Website and admin panel We are a startup into listing various categories of seller on our platform. The key features which we am looking at are as below: 1) Mobile verification OTP signup 2) GPS capture and display as pin on Google Map 3) Display basis GPS location distance 4) Suggestive search when user enters minimum 3 characters 5) Chat between user and seller and Chat history 6) Product cart 7) Subscription transaction between seller and my company 8) Facility for seller to load offers and notifications 9) Privacy settings for seller ad display ( distance / contacts) 10) Buyer following seller 11) Dynamic live location display of seller 12) Seller listing under different category. Each category will have different questions. .... other small features to give best user experience Let me tell that we are not e-commerce company as its generally get confused. There is no financial transaction between buyer and ourself. Only seller needs to play listing fee to list their business. Let me understand the cost and time required to develop this