I have my main tank in the entry hallway (110 gal) with a hole punched in the wall behind to the garage. That's where I have my sump with skimmer, pumps, ballasts, frag tanks, ATO, and RO unit. It is also conveniently placed near my W/D hookup for water source and drain.
I'm going on my second summer with it setup like this. No heater was necessary in the winter months, and during the summer, I noticed no significant temp increase that couldn't be handled by blowing a fan across the sump.
Now, the garage will get extra humid in the summer months because that is where all the evap is going to take place, so if it is something that you are planning on doing, make sure you plan for the drywall to rot out if not protected (water barrier paint of some kind). You might also plan on incorporating a vent of some kind to help remove the excess humidity to the outside, like a bathroom fan. It won't last too long with the salt, but that is much cheaper to have to replace periodically than having damage to your walls.
I'll try to take some pics this evening. Hope this helps.
Jim