I'm new to this site and glad to have found it and I think I may be ab le to add something to this conversation. I have been living and traveling in a 1975 Ford E-100 for three years now and this year as she reaches 40 yrs old I am pretty sure she also has clocked over 300,000 miles(odometer stopped working at 245,000...well 45,000 for the third time.). I think this question you have asked has too many factors to really give on yes or no type answer. Rather I wouls look at it from a more personal point of view.
Ask yourself these questions:
-Do you know vehicles(how to fix, what to look for etc.)?
-Do you like working on your own car/truck/van?
-Do you have all the tools? Place to work?
If you say no to any of those, you're gonna hate a high milage vehicle. Also I heard mention of older vehicles, as someone who never takes their rig to the shop I don't usually like to get anything newer than the late 70's. Also you want to know little things for instance I have a 3-speed C6 transmissionin my van, generally regarded as one of the most reliable transmissions of all time. The later 80's model Econolines have 4-speed transmissions that in their day did not recieve the same reputation for reliability and are also more expensive to fix when they do go out. Buying a high milage vehicle that is known to have a reliabe drivetrain is important, I mean I would take a ford, chevy, dodge etc with 200,000 miles over a Yugo with 20 mimles on it. Basically do your own research for what would work good for you. Also look for rigs with rebuilt major components, my engine and transmission were both rebuilt at some point in the past, just try to get the info on where the work was done. If uncle Jimmy did in the backyard you might want to find another vehicle, but then again sometimes uncle Jimmy does a fine job. If you can, take a mechanic with you to look at vehicles that have had that much work done.
And FYI in 50,000 miles my 300,000 mile van has only nickel and dimed me out of a few hundred dollars. A few brake pads, a wheel cylinder, master cylinder, a solenoid, starter, carb rebuild, windsheld wipers and of course many oil changes. Not really that bad since I enjoy the work and it doesn't cost much. Need to get a few things at the junkyard but haven't gotten around to it, little stuff like door handles and a wiper switch($36 at O'reily no thanks).