Provide a good estimation of the cost of developing your mobile app

I will give you an estimation of the cost of developing your mobile app. The estimation will incldue a price estimation in USD with an estimated accuracy of +/- 10%. The estimation will also include a total time estimation ( no of days from start to finish).
At an additional price of only $ 10 I will give you a detailed breakup of the project phases and the estimated time lines & cost for each project phases.
For an additional $ 10, I can point out the 5 imp points you need to watch out in your app development process and or features you should included or exclude from the app.