In another case of failure to ask the consequences before taking action, we recently had to tell a client that gifting a rental property to their parents locked up the 
suspended passive activity losses they had on the property until the property is disposed of by their parents.
What this means is that a passive loss carry forward of over $100,000 (which would have become currently deductible had the property been sold, reducing their current tax bill $22,000) would not apply, at least until the property was sold by their parents.
Had they asked, they might have decided to sell the property and buy something more fitting to gift to their parents, or just sell the rental and then purchase a second home for their parents to live in.
Being tax smart means asking the right questions before you take action, not after.