Back-calculate Capital cost for cash-out refis

[Raj Gandhi]

I'm trying to calculate purchase cap rate of my older rental(s) in order to evaluate a new possible deal (8%).

All of my other rentals were purchased with cash, rehabbed and then cash-out refi.  For capital cost, should I use 25% of the appraisal (assume the refi loan was 75% loan-to-value)?  The reason I want to do this is because some of the previous deals I was able to refi more than my actual cost of purchase + rehab.  While it is nice to have infinite cap rate, not many deals like that are available.

I've hit the limit of properties that I can cash-out refi conventionally, fyi.