Addons that save info to server?

How can I set up an addon so that it saves player-specific information to the server like darkrp’s money system? Looked around on google for a while and on and the new gmod wiki but couldn’t find anything helpful.

There are no such addons nor there’s a need for them. DarkRP should automatically save money, if it does not, you fucked up something on your server or this is a bug with DarkRP, in which case you report it to its creator.