Amazon's search for its second headquarters may have 20 cities' business communities buzzing, but it has caused concern in other circles.

Chief among those concerns is what sort of impact Amazon HQ2 would have on the affordability of housing in whatever city is chosen, and a new Zillow study attempted to predict the effects on median rental rates in each of the 20 finalists.

Amazon estimates that its second headquarters would bring 50,000 jobs paying an average of $100K per year, which affects each potential location differently depending on its current population and housing stock, both in terms of volume and affordability. Only long-shot candidate Indianapolis would see no increase in rental rates, according to Zillow, due to its abundant and affordable housing stock for both renters and homeowners.

Nashville and Denver are projected to see the largest increases at 2.4% and 2.3%, respectively, while Chicago, Toronto, Atlanta and Philadelphia are projected to have the smallest increases. They would not see as severe of an impact due to the assumption that their existing workforce is deep and educated enough to be hired, thus not adding to any expected inflow of affluent residents.

What Zillow is unable to predict is a major reason why Seattle has seen such an affordability crisis in the past decade: the likely conglomeration of businesses that would follow Amazon to the HQ2 host city in order to work with the e-commerce giant and possibly compete for talent.

What would mitigate that effect is if the winning city sets about building more housing, which Seattle was unprepared to do as Jeff Bezos' startup grew into a world-conquering behemoth. Amazon claimed to have contributed $40M to affordable housing in Seattle, according to the New York Times, and has pledged to work with whatever city it chooses to preserve affordability.