Well, that depends on where the apartment is, how big the apartment is, how old the apartment is, how accessible the apartment is, what type of apartment it is, how nice the apartment is, and a number of other factors.
Want to live in the country, in an old falling apart building with only a bus stop within 30 minutes walking? I could find you something for less than $200/month.
Want to live in the heart of Tokyo, within a minute of a station, brand new building, great view, etc - count on $5000+
Where do you want to live?