i'm new to this plaster world and wondering about starting up and learning as much as i can as a sideline business. wondering if a 2-day workshop (rivesto-marmorino) is worth the money, how long it would take and how many friends' rooms would i have to ruin before i actually knew what i was doing and could begin to offer my services for a fee? how many of you are laughing already? anyway, any advice is welcome!