Radio/tape Cd Player problems of the 2002 Chevrolet Trailblazer

I just purchased this 2002 Trailblazer sept 30 2006. . It was November 22, 2006- the 4 wheel drive indicator lights were blinking when I put it in reverse. The onstar lights were on. The seat belt lights were on. Later the next day, my father got in my vehicle to move it, when the brake sensor came on and wouldn't go off. He didn't use the emergency brake. My father called apple chevy in west york PA to see what they could do. The 24th they called and said the vehicle needed a e. B. C. M. ( electronic brake control module ). I have a 9 month old son. I get to go pay for the bill, and it costs 930. 25 for a vehicle that wasn't that old. It does have 144, 000 + miles but it was well maintained or so I thought. They did a car fax and it was clean. Or so I thought. Apple chevy in west york wouldn't help with any cost repairs. They said when you get an as is vehicle, its your problem. Well after 4 vehicles that my dad bought from them, we are no longer customers. Me being a hot head, my dad told me to not say nothing and be nice. I kept my comments to a low roar. I called the general manager and he said an as is sale is what it is. I got no satisfaction. But a comment I said to him was- what if it was your wife and son what would you do? he said I wouldn't buy an as is vehicle. I basically asked if he wanted some lemonade from the vehicle I just got. I said well I must have sucker written on my head and that next time warn me about getting more ky for the screwing I just received. He basically said sorry I feel that way. We could bring it back and get something different from them. But I basically said no and hung up. Still the radio malfunctions, the 4 wheel drive may work sometimes, the vehicle acted like it was in neutral. Then after being towed, it acts fine. So at present, it sits in my parents garage not driven with $ I still pay for insurance and payments. I did hear a grinding from the shifter when putting it into drive. I don't trust it. Thank you.