I would Strongly encourage you to use a travel agent. There are specialist with Royal cruises or just cruises in general. It takes someone who is familiar with cruises and groups to make sure it is booked correctly. You also need to book pretty far in advance to get the best rates. When booking more than 8 cabins (and every group of 8 cabins there after) you get perks or amounts to even equal free cabins. You will also need all legal names, DOB's, special food allergies, location they prefer on the ship (and more important can everyone agree on a ship, with varied ages, I would say do an Oasis or Quantum class ship). Once you have all that information, you should be good to go. They can create the booking, while waiting for down payment. Typically up to 5 days after you have held the booking.If you have any questions, please feel free to reach out to me.