I know that I do not have stars and its a big project so you will hesitate to give this project to me. But trust me, I have done many projects like this. The only difference is that I have started this on freelancer. Please do have a contact with me once. I will make you understand all the things.
No, any extra cost.
Once this project will be assigned to me, you only need to have a view that everything is going nicely or not.
If not delivered on time, I will refund 25% of the deal amount and complete your project.
Quality will be assured fine and nice.
Please have a look and at least chat with me about this project.
If you won't be convinced with me after chatting then you can let it be.
As I have already made this kind of app and do have sample for you.