This is exactly what I'd like to do through Airbnb, as well. Hence, that's why I searched for a solution and ended up here. Me too, I now delightfully have pages and pages of previous guests over the last couple of years, and I'd love to send them out a message, now and again, at least more than just for Christmas, to give them updates, remind them I'm still here and expanding, and even events coming up in the future in my local area. What a great idea hey? I think that I'll suggest this to Airbnb. Likely, I'm not the first, but if they know many of us would like this option and why they'll add it.