In fact I just an appraiser visit one of my flip projects today who mentioned factoring my smart home tech into the valuation.That being said, there are cases where it can make sense outside of those parameters.. if your target buyer/tenant is a younger millennial you could invest to make your property stand out and be more marketable, and also reap the operational benefits (and perhaps even cost savings) to boot. 

But housing demand is insane now and will only get worse if millennials finally start to buy.

Net population growth (for now lol - Trump), low interest rates, large numbers of millennials forming families, low inventory of RE for sale, etc.  

I would suggest maybe looking into University City which is just minutes away from downtown and in a hot pocket of college students and millennials.

(Millennials: last to arrive, first to criticize)

You should see what is happening downtown for yourself everything from 99.9% occupancy rates, new business development, world class chefs, casino, lake, river, beaches, millennials are moving into and staying  within affordable downtown, major sports, new convention center and much more - its really AMAZING!!!!

Millennials I believe are not interested in buying.

They will be much more affordable and where one of the largest populations, millennials are going to be able to live with access to amenities, transit, and quick access to downtown.

If I sell tennis shoes to millennials (ages from 20-30) that's pretty niche, but even then I can go further.

Area/location could depreciate instead of appreciate - for example, in a lot of cities, people are moving away from the suburbs and into the city (as that is the trend among Millennials).