I lived for 25 years in a house built in 1790, then a year and a half ago moved into a newly-constructed house. I have some pretty strong thoughts about this, to the degree that if I knew then what I know now I would certainly have had a discussion with the builder or might have bought a different house.
- Wiring - there should be ethernet at least to every room
- Space - there should be a network closet or equivalent where the optical fiber internet enters the house
- Power - there should be plenty of outlets; any counter space should have them even if no use is obvious. Same goes for toilet rooms.
- Color - this is a biggie. Outlets and switches should be WHITE. My new house had light almond. Many smart switches and outlets are available only in white, leaving me many less options if I didn’t want to replace tons of dumb switches/outlets as well.
Without those things, it’s hard to build a smart system, and those are (except for color) likely things that would appeal to a majority of buyers who aren’t interest in smart homes.
It might make sense to put in good smart versions of things that are expensive to replace, such as exterior locks, thermostats (ecobee, higher-end Honeywell), garage door openers, and ceiling fans, in the first place. Ideally those would be controllable with either Z-wave/zigbee and a wifi app for people who just aren’t going to use a hub.
Apart from those, I think what you want to sell is possibilities rather than specifics. I have my own (strong) preferences that likely won’t match someone else’s. If a buyer is already familiar with this stuff they’ll probably bring a hub or want to set up their own. If not, you’re probably just asking for limitless phone calls. Maybe work out a deal with a local person/company that involves a credit that would cover a hub and a couple of dimmers to get interested buyers started but would waste less for disinterested ones.