Suggestion it is,
Maybe limit the partners you can live with strongly, 1-5(?), depending on how big your sweet home is.
Home Sizes i could imagine: Flat -> House -> Villa -> Mansion -> Castle
Ofc real estate should be priced accordingly to the status it represents.
The special equipment or furniture you once mentioned could be compatible with all of the above.
I'm not too concerned that it will become the same as the care home as it already feels very differnt.
Personally i'm very much into the "Castle and Her Majesty" theme - fat majesty ofc.
A Castle and it's lush Gardens would also be a nice Bright counter part to the clustrophobic and Dark Underground Lab.
Glad that an, much brighter and more cosy, alternative route compared to the "care home and lab" was already announced :)
PS.: Looking forward to be able to move between towns with the special person you live with. (as discussed before).
regards