My shop is a typical stick built building with 10' walls framed with 2x6s. I used I think R13 insulation in the walls and like R30 in the ceiling...all fiberglass. It stays pretty warm. I would probably use spray foam if I had built a pole barn although I'd probably try to do it myself... I think I had about a grand into fiberglass, having someone spray foam would have been 2-3 times higher than that. Kinda depends how warm you want it... I wanted to be able to make it 60 or 70 degrees inside when it's below zero outside.
Dunno what to suggest for a lift. I should have done 12' or 14' walls, my next shop will be bigger and taller... I'm basically in the same boat, I could do a shorty 2 post but that would be mostly useless for my purposes since I can't stand up underneath it. Might as well just do a rolling scissor lift... either way I'd only be changing tires or oil with it so what's the point. If your rafters are open and/or far apart, a 2 post positioned just right could be made to work though, you could get a cab between them. My buddy's pole barn rafters are like 8' apart, plenty of space.