Quering Regarding Real Estate.

Dear Sir, You can discuss the matter with local advocates and peruse all the related websites and prepare your own terms and conditions and to be placed on your website/app.

an agreement or POA may work for you

you can take POA from A,/B to enter into an agreement in relation to the property with anyone through your app

you can become an owner to any extent but to enter into the sale agreement you would require consent of Aand B also,

1. to become the owner of the property you are required to obtain the ownership documents, 2. if you pretend yourself as an owner without the documents you can face legal complications, 3. you can work as a commission agent rather owner, 4. simply present yourself as a consultant

Move ahead, post complete facts