I will answer as it relates to traditional BRRRR, in the general case there are additional options.  1) Do not perform maximum cash extract.  

Use the actual NOI, not the pro-forma b/c that is how the property is ACTUALLY performing.

I am very happy with the performance of my portfolio - all my properties are between a 10-13% cap rate.

Personally I only use my HELOC on short term projects like flips, new builds and BRRRRs where I know I will be replacing the capital within months.You may be better off waiting a year and save up more cash or liquidate your index funds if the returns on a property will be better.

My wife and I only have <5 properties we are self managing.

Again, these are normally in the lower tier  neighborhoods that rarely perform on resale as their appraisal may suggest.

If you and your husband can perform the same line of work in another state like Florida, Texas, Nevada I would move out of CA as soon as possible. 

I only have 2 properties, and each is in a separate LLC.

You can also check online resources like BiggerPockets or Roofstock, which offer general CapEx guidelines based on property type and age.These methods should help you perform a solid preliminary analysis.

At the time there were limited 3 BR rentals in the neighborhood, but achieved such high rental rates the properties ended up performing better as rentals than as a for sale project.