I checked the prices from few car rental websites, and I discovered that OTS offered the best deal. The price from Hertz was few times more than OTS, so don’t go with that.
Basically, I went to the OTS official web site and select the car which I wanted to rent. They were running some promotions, and you may see it clearly on the home page.
Surprisingly, there was a price difference between the Japanese (lower rate) and English web site. Therefore, I suggest every one should compare the prices before booking the car. You can use google translator to do the work for you.
Once you have book your car, you may also rent a pocket wifi from OTS as well, just remember you can only pick up the pocket wifi on the day when you pick up your car.
You may select to pick up the car in many locations, if you would like to get it on the first day of your visit, you can select the store near Airport. They provide a shuttle bus at the airport, it takes around 15 mins. Otherwise, you may select other locations to pick up your car, such as the one located in Mercure hotel. This place was not as busy as the one near the airport, if you want to have a faster service you may select any locations but the airport one.
When you pick up the car, make sure that you check the car if there is any scratch or any defect. Let the staff know about that and they will mark down the condition on a piece of paper.