Do I determine the the cost basis for the home I've started renting out based the most recent refinance or my original purchase statement years ago?

[Mike9241]

depreciable basis it's the lower of fair market value the date you put it up for rental or your cost including improvements.  the value of the land can't be depreciated

[Cynthiad66]

The property's basis usually equals the original purchase price plus the cost of improvements minus any depreciation. This includes depreciation claimed 1) from having a deductible home office while you lived there, and 2) after you convert the property into a rental. Rules for depreciation and loss on sale purposes.

Land is not depreciable so land should be deducted from Basis for depreciation purposes.