I rent a MIFI from rentafonejapan.com every time I travel there. I tell them my hotel and day I want it and the packages is waiting for me. It comes with a prepaid envelope so prior to leaving country I drop it off at the front desk or at the airport and I'm done. Very easy, never had a problem. You can also rent Japanese cell phones from them. The portable WIFI is a must for using Google maps while traveling. I've also found if there are two of us..if we both have a MIFI, we can use a messaging app to contact each other when we are doing separate things. Saves $ compared to an international plan.