Here is my situation and goals. How would YOU make it happen?

[Josh Kloblo]

Hi All,
I've been lurking on BP for sometime, and it is absolutely great. This is my first post (sorry, have not yet done the introduction post), and I'm hoping to receive advice from some of the more experienced investors, specifically what they do if they were in our shoes, assuming the same goals. I hope this is the right forum.

A little background:
My wife and I are 30 and 31 years old. When the housing market tanked, we recognized an opportunity, and decided to jump into real estate in 2009. We were not (still are not) real estate experts, so we kept our strategy very simple and conservative -- accumulate single family foreclosures at a significant discount, make improvements, and rent out (mostly Section 8). Everything has gone great thus far. We also flipped approximately 10 homes since 2009.

Our situation:
I work a full-time job (make about $110k/year), while my wife handles the real estate business. We own 11 single family rental properties. Each property cash flows -- combined, they currently bring in about $36,000 in cash flow each year. We've invested all real estate profits back into the business. We have no debt beyond real estate. We have approximately $600k in equity across the properties. In addition, we have an operating account at the bank with a little over $100k.

Our goal
In the near future (within 2-3 years), we'd like to move into real estate full time with an income of atleast $100,000/year (and grow from there), and we feel that we're on our way. We're willing to work it as a full-time job for the foreseeable future, and actually enjoy doing so. However, we're questioning whether we're doing so in the most efficient manner? On one hand, we feel comfortable with our conservative strategy, but on the other, we wonder if we could, or should, move to a more efficient, yet still conservative strategy such as apartments.

Thanks in advance for any advice you are willing to provide. I'm not necessarily expecting someone to outline a strategy in detail, but to be pointed in the right direction in terms of what to further research and learn would be great.