Yeah, but lot of good inspection places pick upon these stuff. For mechanical they do a comprression test, oil analysis and some other stuff. A buddy of mine uses them, since he likes saving money by buying 2nd hand, and he has always had good luck with his cars. I'll see if I can find out what exactly they do.
I prefer to buy new and then just run it. The 4R I bought to keep a long time, my BMW I wasn't planning on keeping so I just leased it and had it serviced as per service indicator. It did 14k miles for it's first change and the oil still looked ok, they come factory fil with some sort of Castrol syn I think and I had to add 1qt during the first 14k miles. It did more than 15k on the second oil fill before I sold it and the indicator said that it had 3k still to go, oil still looked good. I used the car mostly for long trips and highway and very little city, which probably explains the length between the oil changes. I sold it out of the lease and still put a few $$$ in my pocket when I got the 4R.
I wouldn't discount syn oils, lots of people have had good success when running them, in terms of MPG improvements, etc.
WHat I dont get is that dino cost like what alomst $2 a qt for good stuff and I can get M1 at Costco for $4 a qt, so per oil change it cost me $14 extra. And since I extended my OCI from 2500 to 5k it costs the same. Iwould also reason to say that I gained about .5-1MPG when I switched, but that is difficult to positively conclude since the 4R just broke in and I added lift and tires. The only way I will know is to put dino in now and see what it does for like 2 OCs, and the go back to M1 and see what it does. SO take .5 MPG extra over 5k miles and see what $$ work out then. Its more or less 10gal and at around $2.30 in these parts you can do the math. FOr me it cost less to use syn than dino due to the doubling in OCI I do from 2.5k to 5k and any MPG I gain is gravy.