I've helped a couple of people contest assessed values and didn't make the connection with the Board of Equalization and equalized value.I love the idea of data crunching on large swaths of information and your use of mortgages (I assume you have an appraised value at the origination date) and HPI are also compelling.Although I haven't played around with it much, because our market is small and pretty homogeneous, I bet I could get just as meaningful information using age and square footage (also available on our tax rolls).

I'll bet if you put pencil to paper, you'd quickly realize your time is better spent focusing on storage or Industrial investing.  

Sylvia, there are no CIA employees living in Douglas County, I'd bet on it!

So best bet then-- a knock on the door could work.

The best bet is to get a good EQ retrofit on your foundation.

One thing I have learned is that betting on appreciation is speculative, high risk and does not fit my investment strategy.

Just like how the casino will let you bet 10,000 on a spin of the roulette wheel - they know they will win over time. 

Not to mention, I bet that 90% of the people on your buyers list aren't serious buyers. 

I also bet they have the resources to try to get out of it. 

Your best bet is to start creating relationships with brokers and apt owners directly.