Buy here pay here

Got my car at a buy here pay here place. When I purchased
it they had implied that the AC had worked. Turns out it
doesn't work to the best ability and now I've had to go back
and forth to get it fixed at the same place by their
mechanic. I've already been there twice 1 time to also
change the motor mounts which I took responsibility for
since it is a buy as is car so I paid for 3 engine mounts and
the labor. They told me after I purchase the car that it did
have engine mounts problems and they changed one of
them before I had purchased the car. now because of the
engine mounts my transmission is going I've had this car
since March. I had another mechanic inspect it and he told
me to get out of the car. I'm supposed to bring it in for them
to fix the AC again and was just going to leave it there and
not pick it up. Would the dealer be able to sell it at the
auction or get rid of it somehow and take the price off of
what I owed when I tell the financing company of how they
sold me a lemon? Me losing days of work 2 keep getting it
worked on and not being able to make it because of the
dependability. Trying to figure out how to get out of my car
without paying so much