I bought a 2003 LS with 105k and sold it with 136k and a 2003 Z71 with 78k this past year and have 87k now. Neither 1 was ever in shop, except for tires and alignment. I did all upgrades and repairs myself, they are fairly easy to work on.
That said. Here are some things to check:
As many fluids as you can.
Lts and Z71s tend to start to rust on bumpers where bumpers caps rub paint (I pulled mine and repainted)
Steering - check for noise (groan) or resistance in one direction, if there steering box is going.
Shocks, might have leaks with 118k
Both front axle seals, these tend to need replacing after 75-80k
Check that all lube joints up front have lube. (balls joint, tie rod ends, pitman arm, etc.)
Good luck.
---------- Post added at 10:03 PM ---------- Previous post was at 09:52 PM ----------
Also, interior-wise. A lot of folks have issues with the front and rear climate control. Throughly check both. I just had to put in a new blend door actuator, mine was clicking and occassionally getting stuck.
How is the leather? Mine had a small tear that dealer fixed before I took delivery, but otherwise, looked new. Most I've seen that are 10 years old look pretty warn. It requires care to keep looking new, so if yours looks good, the current owner took care of it.