In the price range you are looking I found over 100 in my area for sale(50 mile range) and that was just burbs

If the rig has a lot of miles and the push button auto 4x4, check the transfer case thoroughly. The NP 241 magnesium case had an issue on the output shaft (rear) and can develop a crack or hole in the case due to the bearing/race. I had to replace mine at 96k. From the dealer a reman was $1300 a new one $2200 and that was the good discount price. I got a new one from
www.transfercaseexchange.com for $995 on sale

Check the front brakes for proper lubrication of the caliper bolts. If they aren't floating correctly the inboard pads will wear prematurely and by the time you figure that out you will be needing new rotors. Not a big deal on 1500 vs. 2500 models. On the light duty the rotors slide right off. On the 2500s, the rotor is held to the hub via the wheel studs and all 8 of the studs have to be removed to take the rotor off

It was enough work that I still check mine regularly for even wear. The 1500s came with the 4l60e but the 2500s have the 4l80e. Local tranny guy hates the 4l80 as they never break according to him. If you are doing any serious towing I'd go with the 2500. I don't like Tahoes and Yukons as the shorter whee base is as stable for towing and the older ones don't have the 3rd seat. Also the passenger door windows don't roll all the way down. The gas mileage difference is negligible from the Burbs(1500) and for some reason the brakes don't seem to be as good. Doesn't make any sense as it is the same brake setup but I know my buddy's Tahoe did not feel as good on braking as my 98 Z71 Extra cab 4x4. If you can find a deal on the 01 or newer I would go that route as the 5.3s and 6.0s I hear get decent mileage (15-18) My sis has a sweet black 01 burb and with 20s and and a lot of urban driving she gets a solid 15mpg. I guy at work a similar 01 in pewter and does a little better at 16-17mpg. Neither have had any major complaints. The guy at works truck had a washer fluid low light due to placement of the unit and some how the big wheels damaged the the setup with tire rub.
If you want a moonroof, they are really rare in the 99-00 burbs and more common in the 01+ Rigs. The leather in my 99 has a thin wear spot where I get in and out but that is partly due to my rig being lifted. After 106k miles the only issues I have had are:
Transfer case deal from above.
Fuel filter plugged after 96k miles:clonk:
A faulty fuel gauge but it is the sending unit and since they are a combined unit with the fuel pump and about $250 I have relied on my trip odometer just in case. It reads3/4ths full until there is about a 15-20 mile range of fuel left then it goes to empty.
Other than that all I have done is add dexcool and do oil changes. Rig has hauled cars all over the west and was driven daily up until last year. At $100+ per tank I figured it was time to get a SB daily driver. Used to fill it up every other week. Now it gets a tank of fuel about every 5-6 weeks. I get 11mpg unloaded, 9.5 with a loaded open car trailer, and 7.5-8 with the loaded enclosed trailer. I have considered trading it in but it is paid for and I don't have a car payment( and I still really like it a lot.) Also since I own 3 trailers a pickup isn't really needed. Never say never though
I have been thinking about a centrifigal super charger for it