What coding would allow commercial use for 20 passengers?? Seems a big beast if limited to 12!
For more than 12 pax it would come under passenger vessel regs and to operate from Bournemouth pier it would have to be a class 6 vessel. ( This is what the passenger boats that used to run from the pier had).I think it would be fairly difficult to get a rib through the specs due to the ammount of gear you would have to have.if it was a new vessel it would be even more stringent. would also need a boat master licence holder as skipper.
I went alongside the carrier, I survived and didnt even get shot at!!!