@hativered , you raise an interesting question in that whether the application of the de minimis election is per unit or per owner. Please see this ---> https://www.cpapracticeadvisor.com/tax-compliance/article/12372399/the-most-overlooked-tax-deduction...
and
https://www.irs.gov/pub/irs-drop/n-15-82.pdf
Generally it appears to be applicable to the property where an improvement / acquisition is done and the taxpayer/owner is indirect. Thus I am of the opinion that this de minimis amount is for the whole rental unit and not per owner ( there just happens to be four owners at the end of the chain ).
Also I am curious as to why you are treating this "repair/ replacement " that brings the original functionality of the rental unit, as a capital improvement and eligible for depreciation treatment ? Granted, it is tempting for an auditor to take the position that a non-functioning furnace/ A-C replaced by anew one is a capital improvement and your argument could be that 1. a functioning furnace is a requirement for rental and "fit to live" cert by your city; 2. there is no way to replace a broken furnace/A-C with an equally old but functioning furnace/ A-C unit. The point I am trying to make is that I would consider this as "repair " since it just maintains the value and rentability of the asset. If there is an increase in FMV that is only incidental and cannot be measured ( but yes it probably increases the saleability of the asset).
Is there more I can do for you ?
pk
