Shops usually base their rates on qualifications and equiptment. Most dealers are over 100 due to their access to dealer scaners/dealer speacial tools, itbs not avail to public, ect. An aftermarket shop that charges more usually only hires ase ceritified techs, has diagnostic scanners, pays for online service manual,maybe a dyno, smoke machine, ect... some shops charge a very differet rate for maintance than for heavy work andx a differnt rate for diag. Some shops don't charge a lot cause they aren't worth it so they r happy with any one who would bother coming to their shop. I realize you think this is overcharging and that at my shop $85 an hour is a rip off, but most of the customers I deal with hav no problem with it, and I always encourage people to inquire as to why it costs what it does, that way I get to justify the price. my shop is doing great though, thanks for asking.