Buy a house if you like it and want to live in it for the next 30 years. Then you won't care about resale value.
Should we also feel bad for people who decided to short a bunch of random stocks because they had a gut feeling? Mortgages are highly leveraged, and are not inherently a safe investment. What makes them safe is when you're buying something you intend to live in anyway, because you'll always need some form of housing, you're just prepaying for it.
Besides, long term, this will make the neighborhood denser and ultimately increase land value. As long as you hold on long enough your resale value may actually go up. Either way, resale value is not something legitimate everyday people should be concerned with, only speculators. If you're not ready to commit to live somewhere for the next 30 years, rent.
It's not on your property and it was built up to local code and zoning regulations.
[1] http://www.npr.org/sections/thesalt/2013/12/16/249342738/in-...
[2] http://www.kshb.com/news/region-missouri/new-city-ordinance-...
The UK has a lot of Victoria era terraced houses, and in big cities it's pretty common to see the attic converted into another bedroom or an extension build on the garden [0]. If you are the first person in your street doing it, you'll have a hard time getting permission from the council, but if someone else has done it, it'll be a lot easier.
[0] https://static.dezeen.com/uploads/2016/05/landells-road-alma...
https://www.nytimes.com/2015/06/03/nyregion/on-a-block-of-si...
Check out the front-side picture. What do you think would happen to resale value? If you think property owners will continue to buy houses and give up any hope of actionable damages in the race to the bottom of this tragedy of the commons, you're delusional.