I coordinated a group cruise in January 2020. I'm not a TA, just an avid cruiser. I call RC's group department to set it up and get a group number, then everyone called the groups department to book their own cabin and pay their deposit. Yes, we did have cabin's of 3-4 people in our group. We wound up with 14 staterooms (you need a minimum of 8 to set up a group). Each stateroom got $50 OBC, and the primary person who set up the group, got a credit equivalent to one berth in the most common booked stateroom type. We used the money to buy group tee shirts, back packs, reef-safe sunscreen for everyone and a poopouri for each stateroom. We also bought some photo albums from the photo area on ship to give as prizes. We had several big tables in the MDR and had it set up so we could rotate where we sat among the tables so we could sit next to different people each night. We set up our own cabin crawl, slot pull, scavenger hunt, and shore excursions. It was massive fun, can't wait to do it again.