I'm with Bruno on this one. It's really not very difficult.

Is there living space above that room or an attic or what? If there's an attic, it should be trivial. If not, it'll only be slightly harder unless the floor joists are running the wrong way.

And you really shouldn't need to worry about patching and painting at all. Just put in a low-voltage work box and put in a wall plate with some banana plugs.