Welcome Lee,
at 95k it's very young in terms of a montero. Most of them on here have near 250,000 miles these days.
At 95k, service should have been done, if the owner has no record or the records indicate anything other than a mitsubishi timing belt tensioner (hydraulic tensioner) was used, it'll need to be done again, aftermarket ones are prone to expensive failures (interference engine) if the water pump is anything other than an Aisin, the general concensus is to change it out. If there are no records, the seller can tell any story they want but there's no way way to know the truth until it's torn down, so without records, assume it has not been done, regardless of what the owner says, unless they can show proof.
check the back of the cylinder heads for oil leaks, the o-ring back there tends to leak, if it's leaking, that's generally a good indication of what kind of owner you're dealing with, sealing that leak takes minimal effort.
let the truck idle for 10 minutes with the AC on full blast, if the temp creeps, the cooling system needs reworked, after the truck idles for 10 minutes, give it throttle and bring the RPM's up to 2000 and hold them there to the count of 10 (seconds) let off and go look behind the truck, if there's any cloud of smoke at all (blue usually) then the valve stem seals are shot and they need replaced, which is somewhat involved for a newcomer but easy for anyone skilled with a wrench, if that's the case, Viton seals are the way to go.
before you start it, while it's cold, crawl underneath, look for oil leaks, where the exchaust crosses under the transmission the exhaust should be bolted to a plate, that plate diverts leaking fluid from the rear main seal or the transmission input shaft seal away from the exhaust, if you stick your finger up on top of that plate and it's wet to the touch, the engine needs to be removed to do the rear main seal or the trans input seal.
IF it passes all of those checks and the maintenance has been done, i'd say it's worth near what they're asking, assuming it's clean and rust free.
lastly:
buyers guide
http://www.adventuredrivendesign.com/mitsubishi-4wd-buyers-guide/
gen 2 quick start guide:
https://forum.adventuredrivendesign.com/index.php/topic,342.0.html
I'm sure I've overlooked some things, but others will chime in, we've got a great group of enthusiasts on here, the ADD forum and the facebook group:
https://www.facebook.com/groups/1524789904446511/
