There are two types of Ford 6.0l diesel owners, those who have had a major breakdown and those who are going to have a major breakdown.
I highly doubt any of those engines have hit 200K without any major problems.
Sorry, but spoken like a true internet reader. I had an oil leak, small but there, on the '06 I bought a couple of years ago. A Ford certified diesel master mechanic is who confirmed what I experienced; the 7.3 was a so-so engine but nothing special. A 5.9 Cummins would last about twice as long as a 7.3 PSD. From everything I've heard, at 250k the 7.3 PSD is about done. Ford even bragged about them being a 250k engine. I wouldn't give 5k for that truck.
I drove a 12v Cummins for almost 10 years and loved it but everything else on the truck was getting old and I was getting up there in miles. I'm not one who would hop in a 250k mile pickup and tow a trailer 500 miles. Not me. After 2 years not only has my 6.0 PSD been trouble free, but I have it running extremely strong. Still, no issues. The 7.3 PSD I had was
constantly costing me bucks to keep it together. I felt like I needed to just keep a glovebox full of those camshaft sensors and injectors. I gave up on keeping it from leaking everywhere after it crossed 100k miles.
Two friends bought GM Dribblemax engine powered pickups at the same time I bought my '06 PSD pickup. They've both had far, far more problems than I. One is in for a transmission overhaul on his Allison! I'm far, far happier with my decision going with the 6.0 PSD.
However, what you said is actually true; true for every single engine ever produced. None will last forever. My opinion is that the Cummins engine will outlast both the GM and Ford engines by a factor of 2X. Still, being that I like the looks, ride, drive and comfort of the Ford far more than I do the GM or Dodge offering, I opted to drive what I like and not what bloggers blog about. I took my engine advice from a guy who has worked on 6.0 PSD engines every single work day of his life for the last 7 years and in his free time races and pulls with a 6.0 PSD Ford. Like I said, IMHO, the Cummins will last the longest, but that's relative. I'll never drive a pickup with 500k miles on it; ever. With my '06 PSD pulling loads anywhere from 15k to 20k about 50% of the time it's driven, I'll be thrilled to death if I get to 200k with no problems. It's a given I'll get there with no additional costs because it's under warranty that long.
Anyway, I wouldn't touch that quarter million mile pickup for anywhere close to 10k. The body and interior may be nice, but the powertrain and suspension are done unless they've all been replaced. I go to auctions all the time. I'd be shocked if they paid any more than $5500 tops for that pickup.