ye customer....oh wait....i really mean clients, whats the difference ^^
ok can you host a server for me and give me full access to it then so i can configure it to how i like so i can test your theory
Clients / Customers its all the same

Currently iam working on the auth system on my server so i can't help you with a server at this moment,..
But what you need is the following;
- Setup a server with remote access like RealVNC, TightVNC, etc
- Install 25Assist on it and run it in server mode
- If you rent it to your customer(s) make sure that you block everything else (like harddisk acces, shutdown of the system, etc)
If you logon to remote access you can manage your server at the highest level;
If you logon as admin in the AAO2 server you can change your settings there too;
When you are a advanced user you can install PBUCON (from punkbuster) then you can manage your server through web-based pages;
Good luck