Help with used truck?
 

First off, Hello to all!, I'm a long time reader first time poster. I'm not sure if this is the best place to post this thread, but here goes. I'm looking at a 2002 1-ton quad, 4x4, 5 speed that is super clean with 180K miles in Houston, TX. What is it worth? What are things to check for? Do I need to get a mechanic to check the fuel pressure? I haven't been able to navigate the forum search well enough to find what I'm looking for. Any help would be appreciated, thanks in advance. One more thing, the truck is at a used car dealer that has been in business for more than five years.