Re: Check for blacklists
Good point; see my earlier answer about "Boutique ISPs", where you're probably less likely to have this problem.
And also, there are services that automatically check against RBLs for you. The one that I use is RBL Tracker, and their free tier will check a single IP address every 48 hours for you. You can get a notification via Twitter DM (and other means) if your server's found on a blacklist.
Again, for a small home or home office, 48 hours is probably sufficiently frequent, but I would definitely recommend some sort of monitoring like that.