I think my girlfriend bought a lemon and signed an affidavit. can she do anything?

My girlfriend bought a Chevrolet blazer 2004 for 2600 and charged her 399 for tax and documentation fees. they told her nothing was wrong with the car besides the inside driver door panel wasnt connected and the door is wobbly which they told her they would fix before she took it home and they never did. the hood leaks and the speedometer stopped working a day after buying it. they gave her the radio to install herself and the casing to the radio doesnt fit in the car. she signed a contract saying the seller isnt responsible for any repairs after the purchase. is there anything we can do about this?