The problem (as you have cited) is trying to understand what you need (you don't know what you don't know), where to get it, qualifying its source(s), and the validity and usefulness of all that.Pardon me if I've gone into this too much, but I meet many people with the same concerns that you are voicing and this is offered, as much as possible in direct response to your post.Please feel free to contact me if you have any comments or questions. 

Unit 3 - mid-term rental (this would be best for the most private unit as most mid-term renters are more concerned with privacy and creature comforts than amenities)4.

It could certainly be a concern - but depends on a lot of factors - are you looking multi or SFR? 

There are a number of strategies that could be taken with the property that would meet my goals so I wanted to leave it open ended so as to not discourage people from chiming in with their thoughts and ideas.  

I just head up and tell the dock guys and I leave with 10 or so.Sometimes guests take them with them as they are pretty cool and I just have more sitting to put out.

That means, when they are damaged it doesn't eat up the whole security deposit leaving more money to cover other damages better protecting me. 3.

Any of these will leave you in a much better position for success, and provide a greater income while you learn.  

The concern with places like Irvington will be once you move out and no longer owner occupy how do you raise rents legally.   

Having read several books on the art of estimating over the years, I have found that most are good for a few tips that can help but for a newcomer to the rehab business can leave them on shaky ground. 

This leaves $2600 after debt service (PITI).