The DMV website of every inspection state should have a list of things that need to be checked for inspection. I know NH does.
Connecticut doesn’t have safety inspections, but they do have emissions checks every two years. I wish I could find it again, but I once had a copy of a study commissioned by Connecticut that found there were no more equipment-failure-related accidents in states without safety inspections than in states with safety inspections. The study speculated that people have a good enough incentive to take good care of their vehicles because the driver directly bears the consequences of safety problems and noted that in states without safety inspections, basic inspections are often done for “free” when a car is taken in to a shop for ordinary maintenance because of the economic incentive for shops to recommend needed repairs to their customers. It also noted that Connecticut does have vehicle safety equipment requirements and that motorists can be fined by police for violations.
I’ve heard horror stories about shops in New York that use safety inspection failures as a tool to soak customers– who knows though– auto repair is one of those industries that many people are suspicious about because repairs cost a lot and it is hard for the average person to know if the repairs were really needed and if the charges were reasonable.
Now that I live in an inspection state, I find that many shops will do either no inspection or only a cursory inspection prior to issuing a sticker since they view the $30 fee as more profitable the less time they spend on the vehicle– it essentially functions as a “tax” payable to the auto-repair industry. I personally take my vehicle to a shop that I know does a good job on the inspection (I like to be double-checked since I do all my own work)– they’ve still missed some stuff though.
Personally, I think some of the requirements are sort of silly. I once had a fail because the front passenger window would not go up using the switch on the passenger door (it worked perfectly from the switch at the driver’s door). Any safety justification, no matter how stupid seems to suffice– it was explained to me that this could be a problem if the car were in an accident and the door couldn’t be opened. (Why it would be a problem that the passenger couldn’t CLOSE the window is beyond me.) Anyway, I fixed the problem right there by operating the switch about 50 times to wear off the corrosion that had built up from non-use.