Defo a compliment, you seem to know the guy reasonably well, do you think he has the drive to make it work?
As already said there is more than enough work to go around and I doubt you'll lose any customers to him, and can always sell off some of the crappy customers to him 👍
Your biggest error was to do his windows free, had you charged a nominal £5 him would be thinking there's no money in this game😂
Darran