I just bought a used Seville with 90k mi on it. The guy I bought it from made me aware of a few problems. Such as; the ball-bearing in the front right tire is bad(not sure how bad) It makes a humming noise the faster I drive...the faster the louder. Then, something in the engine is growling at me...I don't have to floor it for it to make this noise and that is about the best I can describe it. Can anyone possibly tell me what may be the problem and how bad either of those may be or can get and how pricey?? 
Thanks!
Thanks!