They don't want to hold these properties , so they're just counting these properties and getting them into the second homeowner's hands.

NPR: Is Housing Market Squeezing Out the Middle Class?

If you stay in the house for 15 days or more, not counting days you're really working on the properties, and for more than 10% of the total days it is in use, it becomes a mixed-use property instead of a pure investment property.

FORBES: Second-Home Safety