Please refer to HUD's website to read more about the Fair Housing Act.As @Ned Carey said, there are some additional jurisdictional-specific protected classes that some States and Counties decided to enforce to supplement the national Fair Housing Act, one of which is protection on the basis of income source (aka vouchers). 

Does anyone know when a carbon monoxide detector is needed to supplement a smoke detector?

He keeps the master with the master bath and rents out the other rooms to supplement his SSI income.

My mentors have advised me to either, take out the the washer/dryer hook-ups (cap off) or put in coin-op laundry, protections against countless liability reasons, i.e. laundry business etc...So, after the applicant, now tenant, signed the lease agreement and the supplemental renters addendum, which clearly states in section 'J' subsection '1', "no personal laundry units shall be installed and or otherwise used by any tenant at any time{....}, landlord reserves the right to discontinue laundry access at anytime for any reason."

She'd be more likely to move then.Can the kids work to supplement the household income and support a rent increase?

I got into wholesaling to supplement my W2 income to further my goal of purchasing rentals.

And on another note, I am looking to get into REI to work for myself(freedom) and to create some wealth, nothing crazy if i could supplement my income and quit my job and work for myself i would be totally fine with that.

I am semi-retired and looking to supplement my retirement income with Real Estate and build a business that I can leave with my daughter and Grand Kids!

It can be someone who turned to investing as a stopgap or something they continued to do even after getting another job as supplemental income.

We are both now feeling pressure to supplement our incomes and we are choosing the real estate route.