yes Olivia we booked the voyage prior to the crossing Rome to Barcelona (Ida loves Rome and visiting the Vatican--plus we have not been to five of the ports). Single supp is 25% for the crossing and 50% for the med. Hope you book.
ps..John, sincere wishes for a wonderful & festive Holiday season for your family and Christina and you. (yes these per diems are wonderful, ours came in at about $305pp)