I think a lot of people living outside are looking forward to eat sushi in Japan.
Then, not like the Japanese restaurants located outside of Japan, you can eat sushi either at at sushi bars or running sushi restaurants.
This is sometimes a problem for a small group. For example, if your group goes to a restaurant in Prague, you can choose salad, spare ribs, pasta and pork schnitzel at the same restaurant. On the other hand, you can hardly order ramen noodle, Kobe beef steak, sushi and okonomiyaki at the same restaurant in Tokyo. Usually the restaurants in Japan do not offer wide selection of main courses.
Then, you have to watch out when you enter a sushi bar. Sometimes menu with prices do not exist and the amount written on the final bill depends on the staff of the restaurant. Then, some sushi bars do not accept credit cards.
Therefore if you are not a Hollywood star, I recommend to go to the running sushi. However, running sushi restaurants have two ways of their prices. 1 = All plates are the same price or 2 = The price of the plate depends on the color of the plate. Then, there are three ways of counting the plates. 1 = Pile up the plates and the staff will count them. 2 = You have to put the empty plates into the designated hole which will count the plates. 3 = Automatically counted and you can see your bill anytime at the tablet.
Running sushi used to be sushi on plates were on the conveyor belts and you have to pick them up. However, recently the style has been changed and some running sushi restaurants do not have any conveyor belt but tracks. You have to order from the tablets located at the tables and the plates will be delivered to your table automatically on the tracks by a train. After picking up the plates, you have to push a button and then the train goes back to the kitchen. Then, there are restaurants which you can see the sushi chefs making the sushi but it is usually expensive than the restaurants which you can NOT see the chefs.
The major running sushi chains are Hama sushi, Kappa sushi, Sushiro, and Kura sushi.