So my question is -- what's the typical approach for arriving at a possible purchase value -- as it relates specifically to capturing the NOI in time, especially if it seems to be changing somewhat rapidly?

Doing some preliminary scoping online for example...the following is straight off the MLS…2010 Todd St Greensboro NC3 beds / 1 bath asking price 65,000Taxes 785Seems like it could bring in 700 / monthThose familiar with this market...is this a horrible area, do homes rent out easily, is this somewhat typical? 

Fees are typically based on project type, complexity, sq ft, construction costs & how easy the client is to work with...  

I'd love to hear your thoughts on what kind of mail typically works best (typed letter, handwritten yellow letter, postcard, etc.), how can I quantify the amount of repairs the house is going to require (I have an idea of the ARV by looking at comps in the area, but I wouldn't know what to offer because I haven't seen the inside of the house and don't know the repairs required), and any other advice that you may have.

You'll typically sign those at the walkthrough.

The difference in cost to the tenant to have higher limits is typically very small. 

Typically in my (limited compared to yours) experience most issues come up shortly after moving in.

This is not the approach for a typical investor that is looking for returns.

If you are making all of the payments, that is typically all the bank cares about. 

However, they do typically use low comps so just be aware