It is not that difficult if you are diligent.Here are the simple steps to uncover the reality about demand:Start with the apartments in the area.

Some measure the outside dimensions of the house (LxW) and get a number that way.Here in Georgia, our municipality taxes different types of space differently. ie, they have a rate for heated space (normal house inside) a rate for unfinished basement, a rate for finished basement, a rate for uncovered porch, a rate for covered porch, etc etc.

My experience is I hear that, go to the property and point out all sorts of food left out, dirty dishes and uncovered trash cans or trash not in cans. 

If that is the case then maybe dig deeper and talk with Amy about your goals that you both have for your future and what you want to see / do in your life time that you might not be able to do right now, but your investments will uncover opportunity for. 

What if you uncover hidden expenses?

While trying to figure out what the HOA covers so I know kind of insurance I needed to pay for, I may have uncovered a blatant case of seller fraud. 

In this case, you should resolve going forward to always get an estoppel certificate and interview the existing tenants (to uncover such issues) prior to closing.

One thing I love about both of the investing methods these two authors advocate is that it is not reliant on finding a one in a thousand deal, uncovering hidden seller motivations, making 100 offers to get one accepted, or a hidden reliance on continual price appreciation.

This is a long article but has some good information.I Accidentally Uncovered a Nationwide Scam on AirbnbI reserved a place through AirBnB last year that also turned out to be a scam.

@Alex Antonov I would be very surprised if you have been able to actually uncover undervalued properties in this current market.