You need an annual safety inspection and are subject to a ticket if you don't have a current one. Most repair places and gas stations that do mechanical work can do an inspection. They are very business-like and generally explain what is wrong if you ask. You are under no obligation to have the car fixed by them, but you can get it re-inspected at the same place for two bucks after you have the repair done. If they find a minor repair like a light out, they can fix it for a nominal charge which may be convenient.
You need an emissions certificate to register a car in VA - gas only. It is good for two years. I am not sure about the rest of the state, but in the DC area the test is done on a dyno at 15 and 25 mph for cars newer than 1980. They also test your gas cap and other stuff. If you fail, you can get retested for free within two weeks at the same place. You can get a waiver if you present a statement from a certified emissions specialist (easy to find) that you have spent $460 to fix the problem and still can't pass. If your cat is OK, and the car is in reasonable tune, and the oil is clean, then you should not have a problem.
In the DC area, they measure HC, NOx, and CO. The standards vary by year of car.
I have never felt scammed in either of these tests, but you can get some hard-assed safety inspectors who enforce not just the spirit but the letter of the rules. Emissions is done by entering the VIN into the computer, so there is no interpretation - it either passes or fails.
The safety rules and inspection procedures are required to be available to the consumer at the inspection stations.
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe