Investors & landlords

That is not true.  Renting "personal property" (equipment) *IS* subject to SE tax.  Renting Real Estate is not (which is partially why that is entered in a different section).

This link is specifically aimed at Sole Proprietors filing Schedule C, but the same thing applies for a Partnership.  It is included in your regular Gross Receipts, and subject to SE tax.
<a rel="nofollow" target="_blank" href="https://www.irs.gov/publications/p334/ch05.html#en_US_2015_publink1000313367">https://www.irs.gov/pu...>