The business use was for 9 years of 20% use, ending in 2015.
So while you will report this in the section for "Sale of Home (Gain or Loass)" before you can even start you need to know exactly how much depreciation was taken. To get that amount, you'll need your 2015 tax return. In that return look for the IRS Form 4562 for whatever the depreciation was for. There will be two IRS Form 4562's for that property and they will both print in landscape format. One is titled "Depreciation and Amortization Report" and the other is titled "Alternative Minimum Tax Depreication Report". You will definitely need the first one, but "could" also need the 2nd one.
So until you get those forms and can know for a fact exactly how much depreciation was taken, there's no need to pursue this any further.
