that's what we thought too, at first. But after a few inquiries it appears that it's indeed legal in this case.
John lives atm in a building that's rented out to people with disabilities and it appears that there is a legal gap that allows unlimited rent-rises in such houses.
However, John is not exactly disabled and hence there's no reason for him to stay there. He is vision impaired on one eye and walks with a slight limp but other than that he's perfectly well and a surprisingly quick walker. I asked him ages ago about his injuries but forgot his explanation. I believe it was an accident when he was a toddler. Earth quake, possibly. But I am really not sure.
He's an incredibly nice guy, gentle, caring, always there when you need him, always thinking positive, never giving up - I couldn't imagine a better friend. Or a better roommate or neighbour for that matter. In fact, I don't think I know a better person.
Oh, and he's a Trekkie