I have narrowed down areas based on crime, demographics, schools, jobs, taxes, etc.., i have spreadsheets for costs relevant to my area and am looking at what is available and rent ($/sq ft.) 

A little background on their demographics show they are interested in these 3-4 Br homes based on many factors but location convenience, size and rent price are factors.

MHs are very expensive to maintain due to the demographic of the tenants.

I would keep marketing, maybe try a new channel or two with a different demographic, keep polishing the place up, and accepting applications until you get someone who meets your criteria.

roseville, eastpointe, those are small cities where you can learn demographics for the whole place easily if you dont already know them.  

The tenant demographic is very blue collar, paycheck to paycheck.

The properties are in an A neighborhood, but the overall demographics of the county are flat, and most renters work in the second home service or non-profit economy. 

MORE IMPORTANT than the age demographic for ANY rental situation, however if your 33% rule.  

@Joel Owens  I think its location driven in good locations the space get repositioned since there is no land avalaible.in declining areas like I see in the mid west and deep south that have demographic transfermations and the shopping centers closed years ago never to reopen or reposition.. many that I see have become Monster Church's or simply sit and rot...

There's also a huge demographic of the population who have a mindset that prevents them from stepping outside of what they've known as "normal".