My opinion, for what it is worth...
Price is fair for year, model and miles...but FAIR doesn't mean it's an ideal platform for a build.
267,000 miles is a LOT of miles.
In the $3-5K range you can find 99's and up with HALF the miles.
One major repair on this rig will put you on par with one of the newer rigs value-wise.
Yes, mechanical work was done, but when and how many miles since? "Last two years" could be a lot of miles ago. That list is what you would EXPECT to see on a van with a lot of miles, just to keep it running. That's not a list of carefully inspected and restored/repaired systems to bring it up to like-new condition.
If you will be putting time and energy into the build and keeping it for any length of time, you want to invest in a sound mechanical chassis.
Just like "location, location, location" is the mantra for traditional real estate, "chassis, chassis, chassis" should be your mantra for an RV build.
For projects like the interior, I don't let previous work done by the owner factor too heavily into the price. You don't know how well it was done or if what the P.O. did is what YOU'LL want in your build. Unless the interior is very well done and meets your ideal interior layout and craftsmanship, it's a wash. You'll spend as much time modifying or replacing what they did as you would have on modding the stock interior. Or worse, they may have drilled holes, applied adhesive or irreversibly modded something that can't be easily fixed or reverted back.
If it was me...
For any kind of long-term build, I'd spend a little more on a newer year with less miles.
To more or less urban dwell in one city or in a few cities in a region, where covering miles isn't a concern and your needs are minimal, go for it.