Contractor nightmare - Need advice/help

[LadyJinX]

Hi! 

I'm hoping I can explain my situation in enough detail..I apologize in advance for the long post.

I recently hired a contractor to do a repair on an above ground 12x24 pool. The liner had been damaged during the winter and the water that was in the pool had washed out to the lowest point. It caused one section of the pools supports  and slant to one side a good several inches. 

The contractor deals a lot in text messages and we never actually signed any kind of contract in regards to the work. He originally texted us the quote saying "to replace liner, supplied and installed is $1500 plus tax. Includes repairs to pool floor"  We then asked for some kind of written paperwork in which we got an email with a letter saying ..

"I am pleased to provide the following estimate to replace an above ground swimming pool liner. This estimate includes the following work: measuring for order of the new liner, the purchase of a new 20 (mil) full print liner, the installation of the new liner. New face plates and gaskets for the skimmer, and returns are included in the installation. 

•    Supply and Install new 20 gauge (mil) full print liner             $ 1, 500.00
12x24 overlap                        HST    $     195.00
                                       Total    $ 1, 695.00" 

In short... he started the repairs liner was out and left out for a few days then a liner was installed came home to a pool 3/4 of  the way full. We sent him a message saying the pool was still extremely sloped at least 5-6inches from one side to the other. Plus the liner is riddled with wrinkles all over the base and side posts leaning outwards several degrees. The response was I can't believe it that's the way it was before we fixed it and then he sent me this face .

Several days went by no response and we finally asked so what is happening with the pool? He said he was just going to complete the plumbing and be on his marry way. We tried inquiring about fixing it and why it wasnt fixed and he said he was only hired for the liner  repair didn't know there were structural problems and made all kinds of excuses. He wasn't confident in doing the repairs and I've had to hire someone else to do everything. Which will cost $2400.

We havent paid anything and just got our invoice from him and he is charging full price for replacing the liner, repairing pool floor as per proposal landing us at $1600+

My question is do we have any right to dispute the charges because the liner and repairs weren't done correctly? We were expecting to pay something obviously for the materials maybe? 

I've got pictures if that helps

Thanks in advance!!