I googled the most current local median and average household incomes and went through a few different sources.

Also, I need to know who all is present in the home should there be a catastrophic event, like the place burns down.I make it an automated practice to send reminders to tenants at certain points in their lease term (that require a response) to inform us of any changes to their household makeup as reflected on the lease - and that failure to do so is a lease violation that could result in lease NON-renewal or termination / eviction filing.

Number of vehicles per household might be getting too specific for a national survey.

I interviewed the household names - Coldwell Banker, Howard Hanna, Keller Williams, and Berkshire Hathaway.I decided on Keller Williams because my broker and I hit it off immediately, the costs and commission splits are impressive, decent online training, and I have read a few of Gary Keller's books and feel that I have a similar philosophy.  

the 1% already lives in a large enough house.we have 17 rentals and live in 1k sq. ft house. guess which one takes priority in my household? 

Garage will only be used for the storage of ordinary household items.

I self manage and in 6 of my 8 units, a woman is the head of household. 

Total household verifiable income (minus the business expenses noted above) is what you look at, whether family members or roommates (in addition to full credit/background on all adults in the group).

If it is a two bedroom unit, I would have no problem adding a third person and keeping the rent the same, as long as the new person qualifies.To do so, meet with all parties in the household.

I personally find that hard to believe and there's a lot of controversy around how the population was counted.For example, there are more households in Detroit with active DTE (electricity) accounts than were counted in the census.