Putting a billing on the site

On the site on Joomla you need to screw billing to sell game currency in various online games. In games where it is possible to automate the process of transferring currency to the user - currency must be transferred to the player immediately after payment of the game currency, in games where it is impossible to screw automatic transfer of currency - it is necessary that an SMS notification is sent to the administrator. In any case, you need to notify the administrator and by post. The Joomla version is the last. The code must be written in pure PHP using standard FrameWork Joomla. There is nothing new in terms of code to screw on the site.