If you are accruing 10 or 12% annual interest you have a hard time making enough of a spread to come out ahead. 

I think the increase spread out over a course of time is a great idea, and I see the value in being slightly below average rent.  

What's your typical spread on those??

Principle paid is not income, it doesn't increase your cash return as your loan obligation remains the same or nearly the same, it shows in the balance sheet, not your income statement.Play with your numbers, run spread sheets, imagine what ever you want, you're day dreaming and wishing, don't have time for that and neither do you as it doesn't do anything for you in reality, when you get back to reality study laws, compliance, ordinance requirements like those you asked about so you actually learn something.

In addition to comps, improvement estimates, photos and estimated monthly cashflow / spread (based on an assumed purchase price), what are other pieces of key information that an investor would expect when approached with a potential deal?

Being from Woodstock, I would say that it's hard to go wrong investing in that area as Atlanta spreads out.  

assuming I PM it myself. in the mean time I have a large commercial LOC available that I am using in the mean time with a interest only payment @ 5% which is what is shown on the spread sheet. 

MD is the "if you can dream it, we can tax it" state so again, there has to be a good spread for all parties to have a win-win.  

Once you know what to look for and what areas make good investments, you will have a steady stream of properties to offer and you will be amazed how quickly word will spread. 

Please spread the words about him if you have a chance to avoid future victims.