Did you talk to a single sales person, many or the sales manager? Don't base an entire business on the actions of one person.

Was the deposit to be in cash or credit card? If credit card, the charges can be canceled by the card owner leaving the dealer with nothing.

The dealer has no idea if an outside shop is going to damage the car so they will limit hands on disassembly. ( Re: strip a spark plug and who will be held liable? )

Was the car advertised as needs work or was it pitched as good condition? Some dealers do sell as is / needs work cars.