Plasterers, a friend of mine had a leak in an upstairs shower, his insurance sent a guy to find the leak and repair, this guy couldn't find the leak so he cut a 18" hole in the wall behind the shower, still couldn't find leak so he cut a hole in the ceiling below, well these holes now need repairing, so can you tell me if it's possible to repair so it can't be seen or would it need whole boards removing and replacing, can anyone recommend a really good guy to fix it, I'll need phone numbers as my friend is not on Facebook , thanks