RE: butcher/processor in stafford va
Most places around the NOVA area cost about $80.00 to process a standard cut (roast, steaks, ground). more if want sausage made and so on. The only place I know of that charges you to donate is Linthicum's which is located near the Manassas Battlefields. They use to charge $20.00 to donate, cash only. I really didn't like their entire operation either. Most everywhere else I have taken deer to donate hasn't charged. It gets tough late in the year because of the amount of deer donated though but most will still accept them. I haven't been turned down yet to donate deer.
Last year I went to Gadel's in Catlett, they did a great job, quick turn around and have outstanding summer sausage. Little pricey to get some of the specialities done but worth it when it hits the taste buds. I have tried Fauquier's Finest and wasn't overly impressed with them. I think you have to skin and quarter your deer there.
Good luck the rest of the season and great job on the buck you already killed, I didn't comment on the other thread yet.