What bangers said.
See, we have already solved this problem. We write negative reviews of bad punts. Why not help out? Please share the name of the latest escort that disappointed you after a 70 mile drive.
But anyway, if you agree a price for some services, and the services are not on offer, then it is of course OK to negotiate a new price, or to simply walk. And under these circumstances, if you walk you can still post a negative review.