Originally Posted by
tcook052
Good advice, LapLap. ^
How plentiful are 100 Yen shops? Are there areas where they're easily found such as outside rail stations? I'm on a similiar length of stay in Tokyo and wouldn't mind keeping a few more dollars in my pocket if I can without too much effort. The moderate hotels I've booked all have fridges so if it means stocking up on a few at a time rather than using vending machines for their conveniences that's definately doable.
I've found that most of the non-high end retail areas, particularly shoutengai, have a hyaku yen (¥100) store or two. But you'll find them near rail stations also. Best ones for cheap drinks tend to be the ones near family orientated supermarkets.
But definitely keep an eye out for good deals for the very large bottles of tea and water (tap water in Tokyo tastes vile), you might find an unexpected source, like a drug store, has the most economic options.