I recently purchased a used car. Fortunately I took it to a mechanic before I decided to purchase it. The mechnaic informed me about several issues with the vehicle; none of which were major. I then brought this information to the attention of the salesman in hopes of negotiating a better price. After several mintues of discussion he then offered to replace three items for me in exchange for me purchasing the car at the full asking price. I agreed to those conditions and we both signed what I would call a contract. The document clearly states that they owe me these parts and that I owe them the remaining balance on the vehicle. They completely neglected to replace one of the items and fortunately I found out. Is this a breach of contract? Is the enitre contract null and void? Can I sue?