I am glad to see this thread title hahaha u know, it depends
summary
the minimum allowance should be around 8-10 man/month
that is for house renting and food. To my case I ask for 14-18 for house rental and eating because I don't want to share room with anyone anymore
I want to have everything installed. then I need 6-7 man for oyatsu and soft drinks. 4-5 man to hang out with friends.
So totally I need 24-30 man/month. (22+30)/2=28 man/month
I still not count money to feed gals
It is a big shame for a business runner who "never" knows how "the other gal's lips in a bar taste" << this is just for young businessman. If someone is a businessman, he "should try this out" from time to time. His wife may not look as young anymore