anybody know what the average price for full service in the spa?

Depends on what kind of spa.  RMP or AMP (Russian or Asian)

RMP's tend to be more $$ than AMP's, but that's what I've been told. Never been to an AMP as I prefer the RMP's so I can see a nice Russian or Brazilian chick.

Typically in an RMP it's $180-200 for FS. It depends on the place itself too, but that's your general area.