So far I've read Frank Gallinelli's book - What Every Real Estate Investor Needs To Know About Cash Flow...And 36 Other Key Financial Measure, and Brandon Turner's book The Book on Investing in Real Estate with No and low Money Down. 

Bucket with canvas tool holder liner w/ compartments for hand toolsTape measurePhone: for photo's of measurements of or any type of object weather a plumbing part or screw. and to use  as last resort to call someone else to help :)

Assessed value is a terrible measure of real value. 

(3)How should I measure the opportunity cost of my money tied up?

Patience is important, but consistent measurable action is also very important.

Multi year averages are a fine measure as long as you don't need to pull a large amount of money out in a specific year. 

There are some measures that don't take the debt service in to account, as mentioned above.

Furthermore, the cap rate is only a measure of unlevered return.

Most professional installers use a process that creates 3 separate sealing measures.

Also, when taking measures to protect against having the corporate veil be pierced, is there a checklist somewhere that lists all this?