Used 1998 GMC Savanna 1500 for sale in Stillwater, OK

This is our 98 gmc conversion van that we used to travel to Texas, Iowa, South Dakota, Nebraska, Kansas, and lake trips every now and then! She’s a great Van, starts right up every time in any type of weather. Ac hot and cold, full replacement on the front disc brakes. Less than 500 miles on them. rear brakes are drum brakes haven’t replaced but still work just fine. The A/C window unit also works just fine! I used a solar powered generator to power it. Here’s what I know maybe needs fixed:

There is a leak in the power steering box, I just keep an eye on my Power steering fluid to keep me from paying for a patch or replacement

Driver side window suddenly stopped working. I’m not exactly sure why it just stopped

On the passenger side and rear doors, the key hole is missing, doesn’t cost much to fix I just never worried since the driver side and side door was fine and the doors are all electronically unlocked.

Check engine light is on, code reader says it’s an 02 heater sensor . I would be willing to take it to a mechanic and get a diagnostics and full check over done.