Okay, some things I can just put out there right now, some that I did, and some that I've read.
Just jumping in on that traveling w/ under 2 crowd....
Pack lots of snacks, and maybe even some new ones.
Ditto! Margaret ate dry cherrios, those Gerber finger puffs and goldfish pretzels when she wouldn't eat regular food...which was alot!
Pack some new toys he's never seen before, and pull them out at really, really cranky moments. A diversionary tactic I read on another thread, could be good for the plane, or good for waiting in lines. Perhaps you may even want to wrap them for on the plane since it could take a bit of time for him to unwrap them.
Now this I didn't do and had a hard time deciding what to bring for her for the plane, etc. She didn't really play with much...mainly got into her older siblings things...but for a single child he may need some good boredom tatics.
We use those Spongebob straw cups for him to drink out of. Not sure if you use these, but we bring four. One for juice and milk per day. We still water down our juice (even though DS is three, I feel better about less sugar) and I like to have the control of being able to do that in a non-spill straw cup. The idea is to bring two with you for the day, and rinse/wash them as you go, then give them a thorough soaking/washing that night and your other two are in the room nice and clean, ready to go.
I did bring 3 cups from home, plus some disposable sponges w/ dish-soap in them already. I like those Nuby cups, we had one 8 oz sip style and 2 10 oz straw kind...now my mistake in not having her use the new straw ones at home before leaving, becuse she wanted to keep tipping it back like the sippy and couldn't get her drink at the end...
Always bring a favored toy and blankie from home. One of the most comforting things to a little one is having their own blankets from home to sleep with. I think this will definitely help with the whole bed situation.
YES, YES, so agree...Margaret is a blankie baby so that blankie plus 2 spares were with us and 2 extra blankets for her at bedtime.
And truthfully, I'm a little worried about my little nut with bedrails and he's three!

It's because he's in a toddler bed, and although he hasn't fallen out in a very, very long time, I still worry about him being higher up. Honestly, though, I think you'll be fine with that.
I'm a little nervous about that bedrail thing for an 18 mo...but can understnad the whole 9 nights in a p-n-p...does CBR have actual cribs...like Poly, they were metal. maybe you could rent one...not that you want an extra expense, but if he stnads up in his crib at home or tries to pull out, he'll just be able to sit up and flop right over those bedrials I'd think...don't mean to scrae ya...just thinking out loud
I'm going to go look through my scrapbook from that year and see what else I can come up with.