only rented briefly
If the period of rental was
- Less than twelve months and;
- within a single tax year then;
you are not required to take depreciation provided it was only rented for a period of time within one tax year for the entire time you owned it.
So if you rented it for 4 months in 2015 and then 6 months in 2018, you have to depreciate.
Understand also that this includes all business use. For example, if in the past you claimed a home office for your W-2 job (prior to 2018 of course) or claimed a home office when you were self-employed, you were required to take depreciation for that too. (After 2015 someone claiming an HO had the option of taking a "per-square foot" deduction in lieu of depreciation. I don't know if that counts "as" depreciation though.)
