Poor Customer Service

On Friday, April 5, I brought my old alto saxophone to a music store to see if they would buy it from me. I didn't expect it to be worth practically anything. They took a look at it and said it was worth $600. That was $600 more than I expected it to be worth. Apparently older instruments are worth more. They said they sell instruments on consignment. I would get 75% of the price they sell it for. I told them that I wanted to sell it on consignment and I filled out a form. Before they sell it, they would need to repair it. It cost $85 to repair it. I told them to go ahead and repair it. Two weeks later, I got a call saying they were waiting for my approval to repair it. I told them I already gave them permission to repair it. A week later, I got a call saying my sax was ready to be picked up. I told them it was supposed to be kept for sale. They said okay. Then I got a call a few minutes later saying I didn't sign any consignment form and that I needed to come back in to sign one. Yesterday, I go to the store to pick up the sax because of the horrible service. I see a form with my sax stating it's mine. It wasn't the form I filled out before. The sheet said they would sell the sax for $350 even though two different people told me $600. I mentioned that and the guy said that they could sell it for $600. I asked them where the form was that I filled out when I dropped the sax off. I wanted to see what the form was that I originally filled out. I thought it was a consignment form. They said they didn't have one. How could you not keep any record of a form I filled out? I grudgingly paid for the repairs and took my sax with me. There was no way I was selling my sax at that store. I was horribly upset by the entire experience. I emailed the store manager the entire story. We will see if he responds to me. I'm not expecting to get one back.