I think your phrase of "fixed expenses" that won't change based on rent gets to the heart of my question: should maintenance and capex be a fixed amount per door (and if so, how much?)

It's already against the law, and the law is going to trump anything you could put in your lease anyway.For other things, you'll want to have a catch all phrase that holds the tenant responsible for damages beyond "normal wear and tear".  

If things ever go sideways the plantiff's attorney, with the benefit of 20/20 hindsight, will blow those phrases up in 30-point font and display it for the jury while trying to hang you out to dry.The bottom line is that you need a good securities attorney.  

Customer service seems to be a dying phrase these days, and there are too many people looking to take advantage of new investors.

Instead of phrasing it as "I marketed the property" I'd phrase it as you were "Marketing the contract to purchase the property".

Thanks, Nathan - I probably phrased what I was looking for incorrectly but I do think you answered my question. 

I probably should have phrased the question as "How might I be useful to an experienced investor to make them willing/interested in letting me learn from them." 

Personally I believe that the "your house is not an asset" phrase was developed by Kiyosaki as an overexagerration meant to drive home a point.

I own properties in South LA... they give new meaning to the phrase "hands-on" management. 

You're leaning a lot on the phrasing I used here rather than on what is actually happening."