Can you basically repair a mainboard?

I got the message earlier that a friend's laptop probably has a defective mainboard. She changed the fans herself and after they didn't start up, the laptop was taken to a specialist. This then made the diagnosis "fan or mainboard defective".

If there's now a defect on the mainboard, is it possible to repair it or should you look around for a new mainboard?

I hardly think that as an unspecialized person you could fix something like that.

Replacing the mainboard is of little use with a Laptol, since most of the parts are already soldered and would therefore also come away