@Sextrap
So after literally scanning through the maps and events, scouring for the switches that actually work for the repairman, it turns out that I can't just break open the door, as both of the necessary switches are turned on by in-game events and scenes that are mandatory to completion.
The route you must take is:
Step 1: Defeat the Alp in the cave on Harmonia Road West
Step 2: Go to Hades Beach and unlock the first RED chest you see, watch the scene
(
These two steps can be done in either order)
Step 3: Go back to the locked house and it should open, now.
I'm also about to upload a "redux" version of the game - basically just gives you a bunch of stuff and takes away a lot of the tedium like levelling and grinding to see the story, if you want to, without needing "comfy" mode on. Also comes with a bunch of new items, like the Bottomless Flask - 100% Vigor and Stamina recover, lowers all Lust, cures all desires and Addictions, and it never runs out!
Seeing as how the developer sold this game for profit, though, I'm just doing this because I hate grinding.