Re: Garage Heat and maybe A/C
In the winter you could use one of those propane heaters that mount to the top of the tank, or the torpedo looking ones. One of those would heat up a garage pretty quick. They can really put out. As for the summer, a couple of fans in the right spots can go a long way, especially when shade is present.
Now if you want to spoil yourself, go with the window unit. You could check into one of those wall pack units like they use in hotels. I'm pretty sure you could find one plenty big enough to work and most of those are heater/AC units combined. I have also seen window units that have a heat pump in them. Cut a hole in the wall over in the corner, and you should be good to go.
I know that you can't run duct work from your house's unit because of carbon monoxide, It would filter back through the duct work into the house. but I'm thinking with a wall pack that wouldn't matter because it's a self contained unit.
If your not going to do any insulating, I personally wouldn't waste the money on a unit. Get the propane heater and a couple of nice fans and make the best out of it.
If you know anyone in construction, check with them. They may have some ideas on what works best in you area. You can also hang tarps to make your work area smaller and easier to heat/cool. Good luck!
Cars, well you see, they are just objects to dodge.