This is true. We've been looking for another 7.3l Excursion with low miles just to "put away for safe keeping". Anything with 100,000 miles or less have all been $20k or higher.
Well, finding a 2002 Excursion 7.3 4x4 Lariat with under 100k is a tall order I know because I have been browsing casually for them. But yea, 20k is about the going rate. That's just too much money for that age even with lower mileage, even if it's holy grail of vehicles.
Even the ones pushing 180-200k are still 13-15k. And some of those are 2wd.