I agree wholeheartedly, I think it's rare that the seller didn't overlook something (likely because of experience, or enthusiasm, not dishonesty),

AND inumerable times I have seen a machine only to find the flaws later (which need time and experience to develop a sense for unless you can bring another MAACA expert along).  

Some members here see flaws in photographs that I wouldn't necessarily catch in a million years and I find that impressive.

I do like sellers who are upfront about all flaws (even inconsequential ones), and I try to do the same, even at the risk of a sale - but even then sometimes things crop up that I missed or forgot along the way (especially after a pin sits stored for a while).

So rather than a rating system, how about some sort of list or guidelines or compendium of things to look for - that helps both MAACA buyer and seller systematically look for things so that they get as close as possible to an accurate description? A way to help newbies ask questions and take a step up the evaluation ladder?

Wayne while I get your intentions, it's not going to work.

It's just too subjective

I know, I know. You're right Adam.  I think I made my point for the moment, anyway.

Quoted from websherpa

Any of above minus 1/2 to 1 point for any physical defect such as scratched
backglass, broken bulbs, bad flippers, bad rubbers, scratched/worn playfield.
Of course after fix, the unit regains its points but it should never really
surpass 9.5 or even 9.0.

I wouldn't dock a machine because of rubbers, bulbs or flippers - or any other "maintenance" type issues.  Wear to the playfield, scratches and other damage/wear however, would be valid reasons to discount the "rating" IMO.

Having said that, outside of Bloomington Gold, rating systems on just about everything are almost useless.