I would definitely explore the FB advertising.

There have been other sponsors that have sounded interesting to me, but I usually listen while I'm driving or running and can't easily stop and write down the name of the sponsor, seems like it would be more effective advertising to list them in the show notes, or to have one page where BP lists all the podcast sponsors so you can go back to get more information.

Most traffic will be on Zillow or MLS.I would try Zillow first, if not enough interest I would do a flat fee MLS listing.FB groups national and local for STR's would be another free place to advertise.

These referral services find flat fee agents in each state and then advertise flat fee MLS listing service to sellers.

However, they perform all of the concierge services including advertising and booking.

what happened to us is we were in trail and the defense proved the county tax collector blew it and only advertised for 19 days..

If it's as good as advertised, worrying about what website links to share won't matter.

I use Zillow and Facebook market place to advertise and find tenants.

(If you advertise at a higher rent, even if it includes utilities, it doesn't show up in some people's searches).

Use all advertising avenues (zillow, apartments, FB marketplace) and you will find what works best in your area.