Look at areas that rents are the highest but houses can be found at a discount (foreclusures, shortsale, for sale by owner.)Once I kick my RE biz into high gear I plan to find off market deals through direct marketing.

I did not know why but I do know there are simply folks who have no clue as to what landlording is all about and are just not geared for it.. 

This again is a financing cost.So if you are just buying and holding investment real estate don't negatively gear!

Can anyone give me tips to avoid physical altercations at my units geared towards low-income tenants? 

Let me switch gears a bit then and present a different scenario: If adding an additional unit is out of the question/or becomes a prohibitively long and expensive process, how would you move forward and try and build equity/cashflow?

Otherwise, some book recommendations (these include mostly books on business/lifestyle or buy/hold investing):- "E-Myth Revisited" by Michael Gerber- "Rich Dad, Poor Dad" by Robert Kiyosaki and Sharon Lechter (this provides a more foundational perspective on money)- "Cashflow Quadrant" by Robert Kiyosaki (further builds on the "Rich Dad, Poor Dad" foundation)- "Set for Life" by Scott Trench- "Long-Distance Real Estate Investing" by David Greene- "The Book on Managing Rental Properties' by Brandon Turner and Heather Turner- "The Miracle Morning" by Hal Elrod-"HOLD" by Gary Keller (geared toward SFR)-"The ABCs of Real Estate Investing" by Ken McElroy (geared toward commercial investing)"Multi-Family Millions" by David Lyndahl (This is on my list of "To-Reads".  

My wife and I welcome any feedback on these areas.Our goals are geared towards our long term goal of 500 units in multi-family with at least $100 per door.

I'm looking to be geared up in the next week or two.

Hi BPers,I'm gearing up for a direct mail campaign and I realized that I was a bit unsure about how a subject to transaction would work in DC, due to the fact that DC charges a pretty hefty transfer and recordation tax of 1.45% on each side of the transaction (2.9% total).

You need SCBA gear to work with it safely.