The WPdeposit plugin will help you run a monetary system on your wordpress website. It allows your users to deposit money on their account and spend them out on advertisement, subscription and other … It is pretty similar to the way envato marketplace members deposit money and buy items. The plugin will also provide tools to send money from a user account to another or admin options to edit deposits of a specific user.
Demo: http://codecanyon.net/item/wpdeposit/500402