For example, 25% percent of households in Bakersfield, CA. are renting their home (per RENTcafé).

Whenever more dollars are chasing the same amount of goods and services, the price will increase.My non-political take: in the short-term, poorer households would benefit with an increase of disposable income.  

These parameters will help decide what kind of yields you are searching for, which you can use to filter down your list of macro markets.Then I would start by looking at the macro market's fundamentals, that is the population, job and income growth over time.After that, I would look to see what the rents and home prices are and how those are trending as well.I would do a similar analysis, but at the sub-market level for the metro area you are considering investing in.Other metrics that I find valuable to understand are household income, poverty, unemployment, and educational attainment.

---------RENTAL CRITERIAGENERAL REQUIREMENTS1.Each adult (18 years or older) must complete an application to rent and background check authorization form.2.Each applicant must provide a valid government issued picture ID at time of application. 3.Each applicant must qualify individually or together with a co-applicant as a household. 4.An application fee of$40 per application must be paid prior to processing the application.5.Occupancy is based on the number of bedrooms per unit.Maximum occupancy is two persons per bedroom.6.No Pets - no pets allowed on the premises.7.No Smoking - no smoking allowed on the premises.We will not rent to smokers.8.No Drugs - no illegal drugs are allowed on the premises.We will not rent to illegal drug users.9.No Firearms - firearms are not allowed openly on the premises.If a firearm is owned, it must be safely stored.10.We conduct full background checks.

They get married to a person with a real job and that paycheck gets dumped into a household bank account. 

I do find, everyone has a different definition of what a bubble is.It is worth noting that median household income in Denver is flat since 2005, when adjusted for inflation.  

Indianapolis median household income is $42,076 in 2010-2014 and has grown by 5.06% since 2000.

@Max Householder--That second paragraph is gold, and I'm going to apply that plan moving forward.

Although there are no foreseeable catalysts in turbocharging household incomes or population growth, there are no foreseeable cataclysmic events that should shake that up.

I grew up in Southeast Houston, Texas with my sister in a single-parent household after my parents divorced.