Sanibel, FL
Sandpebble
2 units on the same booking site (bookings-sancapislandvacationrentals.escapia.com) and at the same location. Each one opens its own page with every way to book it, including the host's own site.
CielStay makes the match, then steps aside: it takes no payment and no commission. Booking happens on the host's site or the platform you choose.