Тут посчитали, сколько стоит разработка приложения вроде Инстаграма. Теперь вам есть чем отвечать, хотя цифры выглядят не очень адекватно.
https://appinventiv.com/blog/cost-of-instagram-like-app-development
#freelance
https://appinventiv.com/blog/cost-of-instagram-like-app-development
#freelance
Appinventiv
How Much Does it Cost to Make an App like Instagram?
Determine the cost to develop an app like Instagram and the factors that affect the same. This guide will help you create a social media app and offer you various ways to monetize from it.