WordPress Multisite plugin

I need a plugin that will be installed on WPMU network. It's main purpose is to bill each user on my network for resources used on the server. Task: Calculate hard disk usage for each subsite and bandwidth. Hard disk usage will be calculated from database size of the subsite plus uploads folder. Bandwidth usage will be calculated from access log file. Here's how I see the billing process to flow: There will be a 14 day trial period for each new account. After 13 days an email is sent to the user to let him know that his account is about to be deleted unless he makes a payment of $10, $20, $30, etc. After he makes payment plugin needs to calculate bandwidth and hard drive resources used by that user on a daily basis. Plugin will subtract the total usage amount from the user's account balance. If user's account balance falls below $2 (or whatever I set) then plugin will automatically send an email to the user to let him know that he needs to deposit more funds. There needs to be a dashboard widget to show user his usage status and balance so that he is aware of it. There will be a link in there to make a payment. Everything should be automated. I will need a settings page where I can configure the root path to access log file and any other settings such as price per KB to charge each user, trial period, etc.