Upper Strut Mount & Bearing sticking

I have a 2005 Buick Rendezvous in which when I turned left it would stick for a little bit and then come back around. I took it in today and they said that the Upper Strut Mount & Bearing are sticking. :banghead:

The cost to repair is over $800, now my car is not even 4 years old and has 64,000. Does this seem correct to have this kind of problem so early in the life of this car?

I'm going to try and get a better quote but just wanted to make sure this sounds correct. Thanks. Also I've had at least 2 bearing replaced in this car already.