Create CSS server software which allows to securely track every kill and death in-game, as it occurs and instantly adjust Players' account balance in real time. Should a Player's balance fall below zero at any point, they will instantly be 'kicked' from the server and will not be able to login again until they have added funds to their account.
Basically clone fragcash(dot)com
Also need an easy to use CMS to approve, kick, ban, pay, and manage players, servers, and cash.
Need to be familiar with counter-strike source and cs:s servers