They say Airbnb is a gainful business now. Real estate agents recommend I should have some flats because they are usuful for rest houses. Many people expect they can supplement their income by managing rest houses. Indeed some employees fall easy victims to unscrupulous businessmen.
Many rest houses registered in Airbnb are illegal. It is difficult to manage legal one, because of cost and legal restraint. They predict the government can’t expose lots of illegal one.
I like to stay in B & B. Unfortunately, there aren’t B& B in Japan. I expect many Japanese run B & B in future. 
My Second Life 