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This is called “segmented depreciation” or “cost segregation”. The IRS doesn’t ask you to do this because they would much rather you depreciate everything over 27.5 years instead of accelerating the depreciation of assets with shorter life spans. But it is a perfectly legitimate thing to do.</p>
<p>I only did it for one building I have because in most buildings I have acquired everything was old (it’s not worth it to separate out a 15 year old fridge worth $50), and it does cause extra paperwork. There are web sites that can help with this.</p>