"Pay me for the door repair charge" is a quote used by a variety of old men in the original Legend of Zelda. Besides, of course, this being an 8-Bit video game, they are really the same man, in the same room, incensed by Link's stumbling upon his domain. When Link finds his room, usually through destructive means, he is required to give up some of his rupees so the hapless old man can fix his door, which given the general monster-ridden status of Hyrule, is a reasonable request.
It is a tribute to the designers of the era, as well as the patience and imagination of the children playing, that so much could be gotten from so little. As a tween, exploring The Legend of Zelda, I figured out by accident that many screens in Zelda had secret rooms. In fact, most or almost all of the screens on Zelda had such rooms. So while playing the challenging adventure, I was thrown into the other lateral adventure of finding the hidden rooms.
Alas, the memory on Nintendo Entertainment System cartridges being what it is, there were a limited number of secret rooms available. Some of them were a moblin willing to give you money. Others were a gambling den. And to complete our fiscal symmetry, many were our titular old man, demanding his door be repaired.
Given that these old men are cowering in dank caves hidden underneath trees or inside of rocks, I doubt that their doors were really that magnificent to repair. It indeed seems like something of a scam: wait until an impressionable adventurer burns down the tree that hides your hovel and soak him for an inflated "door repair charge". But given the state of Hyrule's economy at the point the game takes place, where money seems to circle between monsters, Link and weapons dealers, I guess I can't blame the grumbly old men too much for seeking some income where they can find it.