Hi Jamal, if you want to build a network where a few days/months after it going live you are still tweaking and learning from complaints/mistakes from end users then I'm not the right person who can offer that advice. The internet is an elaborate combination of various protocols that services run on. It is not as simple as a file or print services that has 2 services. And if you get the backhauls correct, you will be achieve the end result that you seek. As an example, Look at your backhaul costs below :

 

100 user ( not 100 clients ) network = minimum backhaul capacity of 4Mbit/s ( On seacom  = 2400USD/Month, On Sat=12,000USD/Month)

 

If you are only interested in end user connectivity, I've given you the main concept in my earlier diagram and also pointed you in the right direction about the backhaul calculations. Do your R & D, all collection of data takes time. When you deploy, the cost of managing a well designed network is almost nil while a poor design means you will spend endless hours trying to fix things meaning keep that first aid kit near you with plenty of bandages and pain killers to patch as necessary.

 

If this still does not help, I'll answer the other questions you had listed and not refer to backhaul at all.

 

Rgds.