When Aaron and Sharon Hase of Arlington purchased their first fixer-upper home two years ago, they knew from the start they wanted to resell it with the goal of making a tidy profit.

During the real estate boom of the mid-2000s, their story might have sounded like countless others, but today the Hases may be unique among buyers. Only a few hearty souls are looking to buy anything with the goal to resell — much less a house they don’t feel certain will hold its value.