Rising urban housing costs have sped an exodus of residents, causing strains in ‘Millennial Mayberry’.

This Raleigh, N.C., suburb was declared the best place to live in America by a national magazine in 2015, around the time Lindsay and Terry Mahaffey were drawn by its schools, affordable housing and quaint downtown. The couple found a sprawling five-bedroom house next to a horse farm for $782,000, half the cost they would have paid in the Seattle suburb they left behind. Many other families had the same idea. Apex, nicknamed the Millennial Mayberry, is the fastest-growing suburb in the U.S., according to Realtor.com, and the town is struggling to keep pace with all the newcomers.

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