DIY go crazy: Like the link, use for both chilling FC and beer. Use the bottom to chill beer. In kegs. Use the freezer to keep the FC AND the beer lines cool/cold. Naturally you will run the beer lines from the garage fridge into the house for a through-the-wall faucet setup. Having built a long draw setup it's really not as hard as you might think.
Something is better than nothing: Put the fridge on Craigslist, even if you get $50 it can go towards a smaller fridge and you're not putting a working fridge into a landfill.
IMHO: if you're not needing glycol for long draw draft or the FC chiller, the freezer is a waste and you're better off with a keezer build than a kegerator build.