Does it have NCT(every car in ireland must have one if it is 4 years old), how many kilometers it has done.And how many owners. Also look at the engine.
If it's used, most likely I have an idea of what make/model I want, and a general idea of what model year. I really look at how many miles/kilometers it has on it, I also make sure everything looks ok under the hood. My dad's the best at spotting any potential problems, so if he wouldn't buy it, I wouldn't 😉 It's always a good idea to get a second opinion!
I also check out the safetfy ratings and if there were any recalls for that particular make and model for that year on the IIHS and NHTSA websites..
I'd also check for a carfax report as well.. And the Kelley Blue Book site for the value of the car used..
I also check Edmunds.com to find the TMV of the vehicle used so that I would have more bargaining leverage and not get screwed on price.. and also see what the editor and the owners of the vehicle had to say about it..
Check the motor, all the buttons in the car, all the window/door motors. Check and make sure the transmission isn't clicking. Check the tires, check the frame. Of course go for a test drive to make sure it goes into all gears...
I'll usually check if the engine is clean. If it's not, it probably hasen't been well looked after. Also check the maintainance log to see if it received regular tune ups, oil changes etc.