Should I update my cost basis for property depreciation each year? If so what can I base it on?

[kric]

I have primary and rental properties which TurboTax shows depreciation details for various assets. If I look at the main residential asset and the cost and land values, I questioning if this should be updated every year. As I understand, the depreciation value should be based on the purchase price (dwelling only) + improvements. I also read in this zillow article you can use your insurance agent's estimate of the cost of the building. It seems then, that I should work with my insurance agent on a regular basis to update in TurboTax the ongoing value to accurately depreciate. Is that line of thinking correct?https://www.zillow.com/blog/rental-property-depreciation-144131/

[StephenL1]

Your basis in your property does not change with increases or decreases to the value of the property.  Your basis is the purchase price plus improvements and less depreciation.  You do you not adjust the basis of your property manually.  Depreciation will increase each year and the software will subtract it against your basis so you don't need to change the amount of your basis for depreciation.