@NGJ @Mike7300 and @JustMe this thread has become confusing because there are two many people participating in it and no two of you have the *EXACT* same scenario. So here's the scoop to cover it for all three of you.
As of today's date (Dec 5, 2019) if you placed your rental property "in service" in tax year 2016, 17 or 18 then you *NEED* to go back and amend those returns starting with the oldest return first, to take that depreciation. You *MUST* do your amending in tax year order, oldest first. Otherwise, there is a ONE HUNDRED PERCENT chance things *WILL* be wrong with depreciation and you'll find yourself in the tax hell of a never ending nightmare with the IRS from which you will never awaken. Don't even "think" about starting your 2019 return until you have done this, or your 2019 return *will* be wrong too. I guarantee it, 100%.
When you start the amending process, each of you start your *OWN* thread if you need help and make absolutely certain that you indicate in your post what tax year you are working on. Tax laws for rental property have changed *DRAMATICALLY* from 2017 to 2018 and if you don't specify the specific tax year you are working on you *WILL* be given wrong information and that will be start of your IRS never ending nightmare.
For those of you who placed your rental property in service in tax year 2015 or before, you can NOT amend tax year 2015 or before. You *NEED* professional help. Period. You *MUST* file the IRS Form 3115 - Change in Accounting Method, with "at least" a 2016 amended return or newer. The form 3115 *IS* *COMPLICATED* and if you are not a trained tax professional you *WILL* do it wrong and start that "never ending nightmare" I keep mentioning, with the IRS. So go get professional help *RIGHT* *NOW* with this before the tax filing season starts next month and all the CPA's, EA's and other tax professionals are all booked up.
