I can tell you about a 98 durango 5.2 auto that my father has had since new. 250k miles. I've had to rebuild the rear axle once. The transfer case once (another mechanics fault, dealer actually) they screwed up a u-joint and it wiped out the transfer case. The transmission once, and this was a ***** to get in and out. I'd pull the motor/trans combo next time. One speaker, one window regulator, one water pump, one power steering pump. Couple of belt changes, never broke one, but since I was there. Standard maintenance. No motor work required.
Around here you can pick up "well" used ones for around 14 to 18 hundred. One in good shape, 18 to 24 hundred. Myself, I have looked at a few as a backup for dad and wouldn't go over 2k. But his is working fine after the trans rebuild and he's knocking on 80 in a couple years. As noted - trans a weak point. Cost more to fix than truck is worth unless you do it yourself.
Unless his is super sweet. I'd sell the bike and go hunt up something you want or like. On the surface, it sounds like the better horse trader is him. But if you're both happy............