M
Mr Tiler
No harm in asking but you'd be better off just quoting for the tiling and getting the customer to arrange for their own plumber! That way you don't have to deduct tax, and pay before you get paid for doing the job!
I wouldn't pay before being paid anyway mate lol... but I suppose it would be better cheers... whatever happens on a job in particular the floor will have to come up as the tiles are on floor boards