What should a good accuracy job cost?
That' s going to depend on what you have done. The last time I had any work done was on a Remington 700 BDLSSDM (stainless/synthetic, detachable box magazine). I had the crown recut, lugs lapped, barrel floated, and trigger adjusted down to 2 lbs. It cost me $225.00. (unfortunately, it didn' t help and I wound up getting rid of the rifle at a gun show). You could expect to pay another 75-100 for a bedding job.
In my opinion, the crown and a good trigger is the two things that affect accuracy the most, along with a dirty barrel.