Poor finish from Builder - what to do about the bill?

donut_breasts

Hi,
I've had a builder and his team in over the past 3 weeks fitting a new bathroom, taking out a stud wall, tiling kitchen and bathroom and a few other plumbing works etc.
He project manages the works and has specialists come in for electrical, plumbing, carpentry and plastering tasks. So far the work has been great, however since he started tiling my kitchen its gone a bit wrong. He has chosen to do the tiling himself as he has many years being a builder, however the first day I came home I could see he was not up to the job. wonky cuts, raised and low tiles and the edging was cut poorly. I pointed out all the errors the next day and he said he would fix it. That evening I could see he had fixed 10% of what I had issues with, so the next morning I then told him i didn't feel comfortable letting him finish and wanted him to get a tiler in. He looked a bit unhappy but agreed. However the next evening when I saw him the tiling had continued and he told me the tiler can't come for 3 weeks and so he would continue.
At this stage the tiling still looks irregular but he had grouted the tiles, which he claimed would hide the errors but I feel has highlighted some chipped tiles. Following the kitchen he made a start on the bathroom tiling. This looked slightly better, but they didn't seal the wall before laying the tiles and the cuts are poor and again some are raised at the corners.
During this week, our wood worktops have been scratched and one has a knock out of the edge. This has made me really angry that they have disrespected my property while doing poor work. I have discussed this with him and he said he would fix it, but I've said I would have someone of my own fix it and send him the bill. He said fine.
Following seeing the bathroom and understanding their carelessness towards my property, I have just told him to stop as I don't trust they can a) finish this without damaging something else and b) make a good job of the tiling finish considering there will be lot of cuts and edges in the bathroom.
They have left yesterday, however they left a nice bill for me covering all the tasks they have done, including the ones I am unhappy about the finish, and ones that they haven't even fully finished like plastering.
I will be contacting him, to push back on his final bill, but wanted some advice as to what grounds I have to not pay for certain things. I believe I shouldn't have to pay for work that is done that I believe as poor however he seems to think the job was done to a good standard. Also as I'm not giving him a 3rd chance to fix it, am I being unreasonable?
Thanks guys, longest post, apologies