I had a similar thing with an Asian shopkeeper.I gave him the price before starting the job & he said it was too much, so I told him to do it himself as I wasn't prepared to work for any less. The cheeky so-an-so asked if he could borrow my ladders & tools !!!
Sure he can rent your tools out at a suitable cost! He can pay your consultancy fee when you give him a risk assessment and safe system of work (instructions) !