Maybe I'm no fun but I'm a say-what-you-mean kind of person so I'd flat out ask him, Dude, you need your stuff and I need my mail so what do you want to do here? If he dances around it I'd say, I'll leave your stuff on the porch and just mail me my mail. Done. Easy peasy BUUUUT, why not use this as an opportunity to let him have a glimpse of how great you're doing?
So, I'm in favor of #1 like this:
You, causally beautiful, smelling nice, music on, perfume, glass of wine, curled up on the couch with a good book. You don't nee to be OUT to show you're GAL and doing well.
He comes in, chats a sec, gives you your mail, you point out his stuff... now the business is done. Now what?
If the convo starts up naturally, awesome. If you're looking for an out, you can say, "well, thanks for bringing my mail, I appreciate it. I'm actually having a friend over for a glass of wine so...." or "I'm actually meeting someone for a drink in a few so I appreciate you bringing my mail but I've gotta jet" or something implying you are grounded, kind, able to be alone but still busy and fun loving. Get it?