If you really want to have own house in Japan, the most important is housing loan. Because it is the hardest loan in Japan, and also it is difficult for foreigers.
I think you already understand this.
So 1st it is better to do housing loan examination. If you will do it, you can know the possibility that you have house.
Everyone who buys a house in Japan always does it. I think it is the same as your country.
1st, " you just do 1st housing loan examination "
It is very simple.
If you will apply it, your planning will be started, and of course, if there is no house that you like, you do not have to buy a house.
Housing loan examination is 3 times in all.
1st housing loan examination is "preliminary examination" 事前審査. This is simple examination but if you do not apply, possibility that you can buy a house is 0%.
Most banks in Japan have severe conditions for foreigners living in Japan. However a few bank are kindly for foregner living in Japan.