I just made the Leap you are Thinking about. I got 2 Libertys for the price of one as a package deal One is a 2005 Sport Model 4x4 with the 3.7 and the other is a 2003 Sport Model 4x4. The first thing I checked was the suspension the 2005 model had been previously Lifted and it was torn up pretty bad and needed to be replace badly (Sagging Springs, Leaking Shocks, broken Ball joints etc.) then I checked everything for Leaks (Oil, Coolant , Brake fluid etc) All in all the 2005 was pretty sound minus the Suspension issues which was fine by me as I planned on putting new Lift kit on it anyways so finding that stuff along with the bald tires it had played a great deal in my bargaining the price down. ( Which I did I paid half of what the asking price was) The Truck also had 220 k on the Odometer but the engine was clean and runs like a top for having so many miles. The 2003 model has less mileage and was over all in much better condition than the 2005 model was but it had some small flaws but I wheeled and dealed and paid half of what they were asking for that truck as well (got it for the wife) I have had both now for about 3 months and I have upgraded dozens of parts on both and I have to say they are some pretty tough and powerful little Jeeps. If you have a code reader I suggest you scan the vehicle while your looking if you don't stop by Autozone during your test drive and they can scan it for codes for you (For Free) get underneath and check the drive shaft and shake to see how much play is on it if it feels really loose well that's gonna need fixing but check the Differentials for leaking as well as the transmission if they ain't leaking then you're pretty much good because chances are the one you are looking at never saw life off road so the vehicle will be pretty maintained. Well hope that helps I know its long but I am very through when I look at purchasing vehicles I comprise a list of common parts (Headlights, Taillights, Shocks, Wheels, Brakes etc) and see what the general cost for maintenance will be as well cause when I purchase a used vehicle I pretty much give them an overhaul and customize them to my designs. But Good Luck I really enjoy the way the Liberty drives and I will keep mine for the rest of my days.