Once we are debt free we want to hit the ground running to avoid, "paralysis by analysis" as @Nathan Gesner mentioned. 

You mentioned the UB neighborhoods.

As mentioned.

They mentioned having two mortgages on the property worth about $400,000 in total.

If you get your system and modeling down and follow what I mentioned above with respect to coming up with your strike price/offer price, you shouldn't look back if someone overpays for the property.

Cold calling is already such a poor-performing strategy. the ONE thing good about cold calling is that you are talking to a HUMAN, building rapport, and asking and answering questions.Now that ONE good thing about it is taken away...Like David above me, no experience, and it would indeed be interesting to see how it does, but that doesn't take away from what I mentioned above.

I ask because as mentioned above if you have an investment that is  going to return 10%+ then does it matter what the rate is in the long run? 

Yes it exists, but as the above poster mentioned, lots of hoops to jump through.

Or did you simply mention it because you're already familiar with that one? 

As @Troy Gandee mentioned use the tax estimator on the County website or call the assessor.