I am not an economics expert but CPI is one way of measuring inflation and deflation. 

IRR is the benchmark most investors use to measure success. 

What Every Real Estate Investor Needs to Know about Cash Flow...and 36 Other Key Financial Measures by Frank Gallinelli2.

Gary helps everything make sense by reverse engineering the goal of $1M income and getting that goal chopped down to actionable and measurable steps.12 Rules for life by Jordan Peterson - This has nothing to do with RE but everything to do with living your life with purpose, integrity, gratitude, etc.

It is a measure of return and risk.

However, I'm unsure how the addition of an ADU would impact the appraised value.Do you have resources around this topic or know how appraisals are measured on ADUs, in CA, if know? 

What do they measure out at?

He also pulled out a ruler stick to measure how high the roof was and told them anything above 6 feet the workers had to be tied off with harnesses on.

Also, I’ll copy/paste some advice I’ve previously posted: My handyman or cleaners take pics, videos & measurements of my rooms.

Err on the side of caution.I also hate it when things are measured in months since a month is not a defined period of time.