You could start by mentioning which Drive train.. 2wd, 4wd, AWD? Then which liter engine your going with 5.3 or the 6.0? How many miles are on the vehicle.. The search feature is full of these types of posts and they contain most of the information your looking for, I made the same thread when I was getting ready to purchase mine lol. Some of the members that have been around a while kind of wear down answering the same thread over the years.. But it's true that the search feature can be your own best friend at times. This being your 1st post, welcome to the forums..
Things I'd look at..
Driving it in low gears and listening for whining, turning wheels full circle and listening for clicking, Checking the VIN# for service information, Check remaining life on rotors, brakes, tires. Make sure all your windows function properly, and seat heaters. Might as well sit in each seat until you have checked every single button in the vehicle. Check for your manual, make sure your spare tire and all the tools are present as well. Check the wheel wells to make sure someone didn't tear up the insulation with oversized rim/tires. I actually take my to get inspected by mechanics before I purchase a vehicle. They should let you take the car/truck for a few hours to get checked out, if your that serious about purchasing it.
