A few more thoughts:

One thing I havn't seen mentioned is waste oil heaters.  I've probably got 10 barrels of it sitting around, if a neighbor used it, I'd give it to him.

With floor heat, you'll need to buy a dandy push broom.  Unbelievable the amount of mud, etc, that falls off vehicles when they're dried out from bottem up.

Doors---we looked at 3 avail suppliers, one was by far the best, we went top shelf.

Openers---door guy explained to me that if same guy was manually opening door, he quickly got the 'feel' of it---with several people coming and going, it tended to occasionally get slammed down, pushed up way too hard--he said power openers would would eliminate about all door and adjustment problems.  Sold me and never regretted it.

Thermal mass:  with a heat loss barrier under and up sides of slab, entire slab stores heat.  We can have power off for a couple days and building really don't cool off near as much as one might expect.  No windows in overhead doors, walls very well insulated, ceiling double insulated.  Used kind of blanket insulation with tough fabric that's probably washable on inside.