it would have to be contingent on trusting both sides to be honest and open re: finances. I'm thinking a little bit more of the groupon model - you pay me for every successful booking (or, booking that turned in to a paying customer). Given how many food places seemed to JUMP on groupon, they could take it one step further and say "instead of one time influx of bargain hunters, we'll manage your website - to our definition of good - and you pay us $x/table"