Are/were you enrolled in one the National Retirement plans - for example kokuminnenkin?
If you have permanent residence and have been working for a number of years (I forget how long) you could borrow from them (at least that was the way it was set up when I was there) to help buy a house.
The amount wasn't that great, but it was an avenue that many used.
I wonder if Citibank or the Shinsei bank will lend to the lowly gaijin in Japan now?
