Going rate 727 rebuild.

I know a guy who worked at both big chain you mention.
At both shippng trans gets pulled. No pump rebuild, just were emery the old steels, new clutches. Don't even take vavle body apart just put it back in with new clutches new seals/gaskets., filter.
Put back in, add new fluid and can of TRANS-X.
I saw a lot of that kind of crap back in the day. Best one I ever saw was a shop that advertised a transmission filter/oil change and service for under 25 bucks. The only thing that was new on that service was a cork pan gasket, if he actually did the service at all. The object for the low buck job was so he could con unsuspecting customers into an overhaul. By the way 340six, this clown on his overhaul would do the same, the only clutches he would replace were those that were done and he always seemed to have a stash of used plates he pulled from cores.