im bout to do the same to my 01 ls. if i found a shop that would do it for 50$ i would take it to them. if u want to do it yo self its not that hard. sand it down with a nice fine paper. prep it about 3 or so coats and u should be fine.
is that shop charging 50$ plus paint or do u already have the paint. it may be even cheaper if u bring the paint