When traveling with three under the age of 4, I recommend:
1) A Residence Inn with two rooms (we stayed in Manhattan Beach and I could walk many places)
2) Activities to keep your toddler busy
3) Eating in more than out
4) Planned activities for every other day
Hotel:Our hotel was just right. We did have two rooms, and one was upstairs, so for a makeshift gate, we used a cardboard box. It worked great! It's too slippery for the babies to climb over, just lay it flat on the steps and wedged up on the sides. I did order two eating chairs that were delivered to the hotel - but word of note - if you attach them to your carseats, the airlines will accept them as "baby gear" usually.
Fun: We made several outings, including the beach, indoor play areas, playgrounds on pretty days, Target every other day, gardens, a museum, zoo, and an observatory. I brought some things for Cole to work on during morning naps. One is a sorting activity. I cut out color circles and put them in a muffin tin. He used tweezers to place pom poms in their matched color spot. But when he got bored of the pom poms, he sorted his tiny Squinky toys (his idea).
Was the trip difficult - absolutely. Were there challenges - yes. Was I tired - unbelievably. Would I do it again - no doubt :) We had a great time and were blessed with the opportunity to go.