Never mind bro, these are lessons we sometimes have to learn and unfortunately some of these lessons may be more expensive than others. IMHO you have already bought the car and spent a huge amount on repairs and can't do anything about it now. It appears that you were dealt a double whammy - on your purchase and on your repairs. Where do you live? If its not too far away and if you wish, you could send your car to Ah Chin in USJ. He does not have a big set-up unlike many others who do Bimmers, but I find him to be knowledgable and very honest. In fact, he has solved many of my problems with my ride that AB could not. As far as I know, he will not change any part unless absolutely necessary.
If you are interested, I can pm you his details. Let him check your ride thoroughly and get his advice and then decide what you want to do. I can also call him and let him know you are coming. Is your name Joe? Cheers