Going back to LLC, If you own more than 1 or 2 homes in which you have renters , its vital to have an LLC under them.

I have just started looking at analyzing deals (as I hope to buy my first property this year), but I have started making a habit of rolling any closing costs into my DP when i calculate CoC or ROI metrics.

The seller is working on getting the house classified as habitable again so that I can buy it, but I don't think they will remove the boards from the windows and doors and frankly I would prefer they leave it to help deter squatters.  

.), claims habitability issues in the house (that he caused), requiring another hearing in a months time etc.  

Being a good investor is like any good habit. 

Wow I really admire you for taking this on and bringing it back to where it is habitable...avocado green appliances are back in aren't they :) 

Welcome aboard Adam - I've just started making BP a daily habit. 

If you do decide to keep them, raise the rent slightly (unless you already have, and/or are at market for the condition the apt was in when they moved in), get the repairs done to insure habitability, and give them a deadline and a cost for replacing the AC filter ('replace AC filter by x date or we will do it and charge you $y as added rent' assuming your lease allows such).  

As far as evaluating properties, these links will get you started. https://www.biggerpockets.com/renewsblog/2014/02/14/70-rule-bible/https://www.biggerpockets.com/renewsblog/2010/06/30/introduction-to-real-estate-analysis-investing/https://www.biggerpockets.com/renewsblog/2013/01/19/real-estate-math/Make a habit of searching the forums for things you want info on.

Additionally, the legal system is set up to favor owners of storage facilities as opposed to being "tenant friendly" like it is in the world of habitational real estate.