J.K. Lasser's Your Income Tax 2013: For Preparing Your 2012 Tax Return

9.8 Counting Personal-Use Days and Rental Days for a Residence

In applying the 14-day/10% personal-use test (9.7), personal-use days are:

• Days you used the residence for personal purposes other than days primarily spent making repairs or getting the property ready for tenants. If you use a residence for personal purposes on a day you rent it at fair market value, count that day as a personal day, not a rental day, in applying the 14-day/10% test.
• Days on which the residence is used by your spouse, children, grandchildren or great-grandchildren, parents, brothers, sisters, grandparents, or great-grandparents. However, if such a relative pays you a fair rental value to use the home as a principal residence, the relative’s use is not considered personal use by you. If you rent a vacation home to such relatives, their use is considered personal use by you even if they pay a fair rental value amount; see Example 1 below. The same rules apply if the use of the residence is by a family member of a co-owner of the property.
• Days on which the residence is used by any person under a reciprocal arrangement that allows you to use some other dwelling during the year.
• Days on which you rent the residence to any person for less than fair market value.
• Days that a co-owner of the property uses the residence, unless the co-owner’s use is under a shared-equity financing agreement discussed later in this section.

An owner is not considered to have personally used a home that is used by an employee ...