I do all my own deer so I haven't thought much about it. One thing I do know is that a local shop has a refrigerated cooler that is available for people to hang theie deer in on weekends, after hours, etc. They get a lot of business that way. Many places aren't open on Sunday's and many hunters don't have a place to hang there own deer. Especially when it's warm. There cooler is actually a refrigerated box trailer. It is a large rail that spins, you tag your deer, hang it up and then come in the next business day to let them know how they want it processed. Convenience will get you a lot of business.
A friend of mine does processing but he doesn't do all the sausage etc. You bring him a deer and he charges $75.00 to skin it and cut it up. He does grind meat but if you want jerky and or sausage he takes it to a local locker and then he picks it back up. He makes a ton of money and can process a lot of deer because he is not spending time dehydrating etc. I can't imagine paying $75.00 to have my deer cut up but he does hundreds every year.