One thing I've learned from traveling is that a little preparation saves a lot of stress later. Before visiting Japan, I read How Much Does It Cost to Live in Japan?
https://www.mobal.com/blog/living-in-japan/cost-of-living-in-japan/ to get a better picture of everyday expenses. I also decided to use Mobal eSIM , mainly because I expected to use navigation, translation, and travel apps every day. Looking back, both decisions made the trip far easier to enjoy.