akeenan hit the nail on the head Macross.
If you are going travel to Japan, and really want to experience all the things Japan has to offer, I would suggest holding off for a while and doubling your budget. If you are going to the trouble of going all the way there for 10 days, whats the point if you have to be watching your pennies the entire time?
The first time I went to Japan, people laughed at my $5,000 budget which was for 12 days (including airfares) and while I had a great trip and thoroughly enjoyed myself, I found I still had to hold back and be very careful with expenditure.
Thesedays when Beer Baron and I travel to Japan, I find that I generally have minimal change from $10k, but then again I have a tendancy to not hold back and spend silly amounts of money on car parts, food and other assorted junk