Hi Davebates and welcome to the forum. I work as a handyman too and specialise in kitchens and bathrooms so there's a lot of tiling involved. The key, as you said, is making the customer happy. Crack that and the jobs will roll in. Quality, quality, quality (oh, and punctuality, reliability, cleanliness, etc !). The pro tilers on this forum are amazing - a great source of information and tips plus some special "get out of trouble" tips too.