My memory is blurry, too. I feel like breakfast was provided, possibly lunch (not sure on that), but definitely not dinner. How much you spend depends on what you do. I didn't do much beyond hang out in my room trying to recover from the jet lag, but some people went out on the town. You probably won't have a GREAT deal of time to be sight-seeing or anything, but you may do some stuff so you'll want some money.
As far as the luggage... are you sure you're not allowed to take a suitcase? From what I recall, you're technically allowed to bring one large suitcase and one carry-on to the hotel, but they highly encouraged you to stick with a carry-on. I did and it actually became quite a pain. It's hot, and carrying a heavy bag around is a lot more annoying than a rolling one. Plus, you'll get a lot of crap at orientation you may or may not want to keep. On top of that, you're supposed to pack clothes not only for the several days you're in Tokyo, but also for a few days after just in case your other luggage takes awhile to get to your placement (most of the time it'll arrive before you though). In short, they're asking you to take a lot of stuff in a tiny space. This is just me personally, but if I had the chance again, I would have probably taken the smaller of my large rolling suitcases for orientation + laptop (free interwebs in the hotel, if I recall) and shipped everything else instead of trying to cram things into my carry-on and having to carry it on my shoulder all over the place.
Also keep in mind, though, that you'll probably be sharing your hotel room with two other people, so it's not especially roomy. They will also provide some shipping labels and such so if you need to mail anything from the hotel (very easy to do) you can.
I don't remember having to pay anything for orientation. In fact, I'm sure I didn't. Ask your CO about that, though, as it's likely another ESID thing.
"In three words I can sum up everything I've learned about life: it goes on." -- Robert Frost