Before purchasing the property I purchased the data from AirDNA to get a sense of what a house, similar to the one we were buying, would do in terms of income per year. 

But this is my personal opinion (backed up by data), not necessarily something everyone should do.

With Google Voice, do you end up using data when receiving an incoming call on an iphone/android when not connected to wifi, or does it just use your phone's standard minutes and texting plans like any other call? 

Just start googling and you'll find all kinds of information and data.

I've been chasing a problem for my younger son that requires me to log a lot of computer data. 

If they really want to know whatever it is they need to know, they can mine the data themselves.

I guess that's all to say that there is not one piece of data you can pick out of an appraisal, but it is certainly valuable information if you know how to read it.

In most markets, finding comparables is relatively difficult, even when you have access to all of the necessary data sources.

A quick comment on the Case-Schiller Index data, with an interesting illustration.

There ought to be an entire BP forum just for people who are looking for probate and absentee owner leads data.