Meghan McCann, a sales representative for a wine and liquor company, has spent more than a year looking for a house in Columbia County, in the northern Hudson Valley, where she was born and raised.

Ms. McCann, 39, who grew up in Copake Falls, less than 10 minutes from the town of Hillsdale, where she currently rents with her fiancé, Joseph Walters, said she was preapproved for a $270,000 mortgage, but “it wasn’t enough.” Every house she and Mr. Walters looked at sold within two weeks for prices that beggared belief.