Depreciation Formula

I am in the process of putting a contract on a Mobile Home Park. I am trying to figure out the depreciation. From my understanding you add depreciation and mortgage interest back into the NOI minus the capital expenditures to figure out you cap rate? What is the formula to figure out depreciation over 15 years? Any help would be great

So- this is a really advanced question… I use the software from http://rentalsoftware.com/ to do that type of analysis.

I think in the ‘bang for the buck’ category, this is REALLY good software…

NOI does not include any debt service (P&I), nor does it include depreciation or capital spending. We use Turbotax (Business version) for all our properties and it handles depreciation just fine.

Bret