Well it wasn't the mail, but the craigslist guy did drop it off: An awesome sliding-door commercial ice cream freezer for $125 ($100+$25 dropoff), big enough to cold-crash three fermenters and chill my sanke. Guaranteed to work, he promises, he tested it out and everything.
So I turned it on to "1" overnight to see where that put the temperature (pending external temperature control).
In the morning, the condenser fan is still running... hmm, curious, should be at target temp by now.
Turned on my probe thermometer: Inside, 50F.
Ambient garage temp was 30F today (weird weather we're having). So... yeah. Not happy. Hoping it's the evaporator fan, because if it's the compressor or anything to do with the refrigerant I'm going to turn it into a planter.
Emailed the dude back, and suddenly realized I don't have any idea who he is. Craigslist anonymized his email. The phone number he gave me to set up the deal was mistyped, and we just wound up doing it over email. I'm actually pretty sure he didn't set out to F me, but I give even odds he's going to be happy to F me now that his junk is in my garage and not his.
Edit: NM, he responded. Still have yet to be cheated on craigslist, astounding...