As an internet based company Viator aggressively promotes its tours. Nothing wrong with that. But if you cancel within a certain time, they keep 50% of the proceeds. I recently cancelled a scuba trip in Iceland, two days before the scheduled tour. EVERY OPERATOR IN ICELAND returns the entire amount if one cancels 24 hours in advance. So Viator did not have to pay the operator anything for the cancellation, but pocketed the money. This is so wrong. Also, if you book directly with the operator, its far less expensive. You are paying way more for Viator to run its business.