The Edenpure looks pretty slick but kind of pricy and I still haven't figured out what sort of current it draws?

The Mr Heater based on its manual looks safe to use for a garage with some fresh air flow required.

I've been eyeballing one at summit that seems close to it:
SUMMIT RACING CLEARANCE REM55PVA - Remington Forced Air Propane Heaters - Overview - SummitRacing.com

but...haven't seen specs for venting yet.

I'm only going to be using what ever I get this and next winter then it'll likely never be needed again. So I'm trying to be practical but not stupid.