Depreciation on private residence turned rental in 2016

[Kevin D.]

My wife and I are regrettably taking a DIY approach to taxes this year (probably the last year we'll do this!) I'm seeking tax tips for depreciation on an SFR that was purchased in 2014 as our private residence then converted to rental in 2016

Details:

• Purchased in 2014
• loan was refinanced in 2015  
• We began depreciating in 2016 tax year, the year we began renting the home as landlords
• tax preparer for 2016 taxes entered basis amount based on 2015 assessment, not assessment from purchase year or for the 2016 assessment
• unsure if bases was set correctly and whether to carry through that same basis or pull current year assessment for this and subsequent tax years
• Turbo Tax seems to be steering me towards using the purchase year assessment for the basis for depreciation.  

My question is this:

What year assessment should I be using for the basis for depreciation?  The year of original purchase (2014), the year of the refinance and year my tax preparer used in 2016 taxes (2015), the year we began renting the property (2016) or last year's assessment and each subsequent re-assessment?  

Thanks!