It is more difficult to find a dock either as a transient or a permanent slip for a catamaran in general, but this is changing fast and will soon not be too much of an issue. In the USA dockage is charged by the foot so there is no disadvantage there but in some places (the Mediterranean for example) dockage is charged at length times one and a half because of the additional beam. We mostly anchor out though, since the catamaran is stable at anchor, our dinghy is big and comfortable enough to get to shore fast and with the generator and watermaker, docking becomes a non-issue