Depends on the vehicle, and how it has been maintained. My '96 GMC is 170k+ and it's driven daily, and serviced regularly. I've never been afraid of a vehicle with a lot of highway miles, something '12+ with over 100k I wouldn't shy away from.
I care a while lot less about miles then I do about other things such as rust belt, snow plowed, used commercially, service, history.
A Toyota Camry from Central Florida that is garage kept and parked in shade at a office that is dealer serviced and is drivin up/down I75 each day might go 700,000 miles, the same car used as a taxi in NYC not so much.
Some vehicles I would not own if you gave them to me such as a 6.0/6.4 Ford truck, it is not if but when they are going to break down.
My 4 wheel vehicles are all mostly used up (and paid for) by other owners. My experience has been that I can get that amount of mileage out of them again with a little respect, maintenance and inside storage.
Just so happens, in my last 30 years or so the vehicles have been Fords. Hard to beat the resources of competition, aftermarket parts, the interwebs, etc. You don't find this so readily with unique, specialty or otherwise lower volume sold vehicles.
FYI - smart move on higher mileage vehicles; High mileage is fine, but always have a backup vehicle.
My '04 F250 has 350,000 miles, has plowed snow since day 1 using big V plow, pulls 10,000-12,000 pound trailers often since day 1, and hauls 3,000-4,000 pound skid of shingles in bed many times. It is 5.4 gas engine and original parts. It still runs fine but uses some oil now days. I never really done much maintenance on it other than change oil. I have put many of wheel bearing hubs on it and have gotten damn good at changing ball joints(every 2-3 years) and fuel pumps.
Some guys talk up Diesels...how they can run forever. Some guys consider an '07 Duramax with 200,000+ just broke in and worth $25,000. The engine and tranny may be bullet proof but you still got the Chevy rust fighting you. If the engine runs 1,000,000 miles but the frame and brake lines, coolant lines, etc. rusts away in 15 years, what have you gained?
I would say the most important thing to look at on a higher mileage truck is the part you cant see without getting dirty. Look under it real well.
If it's a zero clearance engine with timing belt, I consider it high mileage when it's reached the point reputation indicates it's likely to break a belt. To me it seems that's when other mechanical ailments also begin to rear their ugly heads.
I have a brother who brags about all the car payments he's saved while driving his 96 Dodge Diesel all these years. Truth be told he spends over half his weekends either down at the NAPA store or laying in the mud under that thang in attempt to make it road reliable for the following week.
We like to buy lightly used and rub them into the ground. Her 2000 accent was over 250k and still ran/drove great. It was all the 13 year old economy car parts that were falling off.
Driven by other people? Anything over the suggested (major) maintenance mileage. NO ONE does the maintenance.
Driven by me or my wife? Probably 150K would be "getting up there", but we don't drive a ton. Maybe 20K per year spread across vehicles. That's 15 years on a vehicle. I've noticed that these newer vehicles can really pile on the mileage, but all kinds of random stuff starts falling off after a few years.
Still better than the old stuff. 100K was high mileage AND they were losing parts.
Maintenance is everything. Wife's co worker bought a Honda CRV over 10 years ago. She did every service recommend in the owners manual. It had 350,000+ on it when her daughter Totaled it. I Service my vehicles myself and take care of small problems before they become big ones. I haven't bought a New car since 1997, let someone else take that Beating when it's new. 1 or 2 years old for half the cost of new.
+1 that care and condition matters more than absolute miles. Working in a shop I saw 30k mile cars you couldn't pay me to take and when I was in school some elderly gentleman donated a 94 LS400 with 250k that looked and ran like it just rolled off the line (with a 2" stack of dealership maintenance records).
For my wife, slightly less than new: our last car was a year and 3k miles old for about $5-6k off the original price. Let someone else take the initial depreciation hit. That being said, she's gonna have to be awful persuasive to get anything else.
For myself... I'm a mechanic by training and I still have the tools for it. I've had 3 cars under 100k miles (out of 12...15...lost track). one was a fluke, one crossed 100k the next week, and the last was trying something newer which I sold a year and 10k miles later to buy a 10 year/100k mile older truck.
While, it's a car, he is what I do. I have been in outside sales since the mid-80's.
The Wifey likes Caddys. So, every 5 years I will buy a Caddy DTS with around 100K miles. Since I usually drive 50K a year, I can usually get almost 300K miles on it before something big time bites the dust (I just junked a 2006 with 291K). Bought a newer 2009 with 92K last fall and it should keep me going 3-4 years.
My company gives me XXX amount for a car every month.....I am way ahead before it dies.
Honestly with most modern vehicles it's rust that will likely stop it long before it's in drivable. I had to replace my 10 year old 160+k mile Elantra because the front frame horn was rotted through.
I have found 2014-2016 trucks with over 100,000 miles. Some are still over $20k. I feel that's a little high, but I always considered anything over 100,000 miles high mileage.
I started the thread because maybe it's time for me to stop thinking that way.