Auto repair service near Warrenton, VA

My father purchased a car from them recently. It was a good deal and they advised him to come immediately because they wouldn't be able to hold it much longer. He leaves work right away and purchases the car. He immediately goes to the gas station up the road and after he's done filling up, the car won't start. Luckily, his friend was with him and was able to jumpstart him. He managed to get the car home that evening and to work the next day. On his way home from work that evening, the car starts making noises and dies. He managed to get it into a parking lot. So he gets the car towed to a shop (and friend of the family) and told him that it needs a new transmission. My father called them and let them know what happened. They were not willing to negotiate at all. No exchange or reimbursement. My father even offered to pay for the labor if they purchased the parts but they refused. We are filing complaints with the BBB and will be taking legal action. Don't do business with these people.