I suppose that it is OK to give a description of just what the access is like, and allow people to make up their own minds whether it's worth their while checking the place out?

"This charming property is surrounded on three sides by deep marshes and is approached by a precipitous scramble down a sheer rock face before climbing the 137 steps to the front door. The rear door opens directly onto a platform from where the dive into a deep pool is 32 foot at high tide."

This would successfully put off wheel-chair users, probably.