Full Throttle Georgia Jet ski repairs not done, collected money then claimed no guarantee on his work or parts Woodstock Georgia

Full Throttle Georgia

I purchased a 2005 Yamaha FX h*o Jet Ski 22 August 2014 from a private party. I was able to drive the jet ski for an hour at a time before it would stall and become difficult to start. Since I did not know much about jet ski's mechanically, I took the ski to Full Throttle Georgia on 10 January 2015. At the time I got an estimate of $1300 for the body work and free diagnostic engine check.
I left my 2005 Yamaha jet ski with Arthur to get body work and engine work. At the initial visit Arthur asked me to explain the engine performance. I told him the engine would run for about an hour then it would start slowing down despite having the throttle pulled down. Eventually the motor would not start. Arthur called this April and said the Jet Ski was ready a running perfectly. I paid him in full for the work, and when I took the jet ski back to the water and it ran the same as if no engine work had been done. I took the Jet Ski back and told him it has not been fixed. Arthur and his assistant mechanic Josh were puzzled but said they would look into it. Josh called me about a week later and said that my computer that controls the engine was bad. They said it will cost $400 for the evaluation and $1500 for the computer part plus $300 installation. I thought hard about this decision because the jet ski was used, but I didn't want the payment of a new ski. I paid Arthur the $2300 for the repair. Arthur called me on 29 May and said the ski was ready but he advised me I should sell the ski. I continued to question Arthur about this comment and he said this model has an electrical box the gets wet and shorts out the computer system and he could not guarantee his work for this reason. On Saturday May 30 I went to pick up the ski and Arthur said that the ski was running fine but he repeated the story of the model having this defect. I asked him then to take the part off and send it back. He refused and said there is no guarantee on electrical parts. He offered to show me other models to trade for. I decided not to do that. I put the ski in Lake Alatoona that day and as expected the ski has not been fixed. Arthur now has been paid over $4000 to repair my jet ski and it runs the same as the day I delivered it to him. He refuses to take any responsibility.