Renting an apartment could be very troublesome for those who wish to live in Japan. These two websites gives the tips on renting an apartment.
It gives a very clear explanation on how to rent an apartment in Tokyo in 12 steps. MetroResidences is recommended as a solution for those who has difficulties on the12 steps.
If you want to know what you need to rent an apartment slick on the title of the blog to jump over to their blog. If you still have difficulties, contact MetroResidences!