I never let anyone else touch my vehicles, except for one close friend. That's because his diagnostics machine is better than mine, and he an alignment rack!
I run Amsoil synthetic in everything I own that has an engine. My vehicles gets changed at 20,000 miles or 1 year, whichever comes first. I also have an oil analysis done about every other year. So my total yearly oil change cost is between $40 and $60 per vehicle, depending on if I do the analysis at that particular change.
If I even took my 1985 GMC pickup to a chain LOF place, they wouldn't know what to do with it! It has a Flex-fuel 5.3L Vortec out of a 2007 Silverado that also has Active Fuel Management, along with the 2007's transmission. I have a hard enough time convincing people at the gas station that NO, I won't ruin anything by pumping E85 in to my "old" pickup! LOL!! Nothing like 24-25 mpg from an "old" truck!