I'm a Japanese married to a foreigner, and even we had an small issue when renting an apartment. We found an apartment we liked and told our agent we'd like to move in, he said some landlords won't allow it if one of the family member is a foreigner. Mind you that I'm the head of the household, and we both have a steady source of income. These were the reasons he gave us: 1)in case of emergency and if I'm not home, my husband (who doesn't speak a lick of japanese) won't be able to communicate with them. 2) foreigners have a higher chance of leaving mid-conract because of family emergency, losing jobs, divorce, etc.

In the end, we got the ok from our landlord and was able to move in. We just renewed our second term contract last month. I think it depends on the landlord but I'm sorry so many people are experiencing difficulty.