Doutor Coffee (various locations)
If you're like me, you're not fully awake until you have your coffee in the morning. I always have an iced soy (or almond milk) latte pretty much wherever I am to start each day. When I am in Japan, my go-to stop for Breakfast is Doutor Coffee. it's a Coffee chain around Japan and can be found in (almost) every city. They have a good selection of very affordable breakfast items, and a seriously delicious latte! I usually stay in ebisu, shibuya, or meguro, and there's a location in each. My favorite item to get is either the Japanese Toast with butter and jam or the Cheese Toast. Both with a Medium sized latte comes to under $5 USD.