And Osaka, how long in advance do you usually book a hotel?

See when you want to go. For example, March and April are the cherry blossom season, and famous Japanese tourist cities such as Osaka, Tokyo and Kyoto are in short supply. Basically, the better demand was set at the end of last year. If it is relatively off-season, it is best to book 1-2 months in advance. Of course, it doesn't mean that you can't book in advance 1 or 2 weeks, but the discount range and housing may be much less.