A deal where you have little to none of your own capital in the enterprise is more common.   

Replace all the incandescent bulbs with CLFs or LEDs, including common areas.

As experienced self-directed investor @Larry F. gave you some good tips, and it seems that you did a good job educating yourself.As a real estate agent and notary you are considered to be self-employed, therefor qualify for truly self-directed Solo 401k plan.

Is this common practice?

.- Is it common to see good cash flow on these types of properties?

Now, down at those temperatures, your COP will be approaching 1.Here where we have cold winters, code requires an ancillary heat source - electric baseboard heaters are most commonly used - to supplement the heat pump in the dead of winter (we frequently get 2-3 weeks where temperatures are below -20C).In a warmer climates, even if code requires you to put in ancillary heat, you should never have to use it.

To my knowledge that is not a commonly accepted practice. 

I personally dont contribute in the Retirement plan right now because I can always resume when I am making more money, and plan to have other kinds of Retirement plan that will let me contribute a lot more than normal limitation for an employed worker. 

I see UTC as both a draw to the youth and retirees since one is able to take public transportation to employment centers of Sorrento Valley, the entertainment of the UTC Mall, get to Petco Park, Old Town, Downtown San Diego Mission Valley.

Trash, sometimes water, common electric for lights, etc.