HI lucipher - I would suggest that you review this article here: https://una.io/page/view-post?id=178 which will give you a basic guide as to what to expect for a server load at various stages of a sites growth. With that information to support your calculations, you could connect with the major cloud hosting providers and seek quotes for your requirements - you will find that they are very competitive and I imagine would be supportive of innovative startups based in Africa. The key advantage with Cloud Hosting is the ability to rapidly increase capacity to cater for a surge in demand, so there is no need to purchase a big server straight up, you can easily upgrade as your membership grows. UNA also supports remote storage, which will help in economising the server requirements for a busy data intensive site such as you describe.