Answer: City of Portland (and presumably entire state) allows landlords to use SSN but a tenant's failure to provide a social security number cannot be the basis of rejection.
Even if well meaning, the leasing agent could be accused of discrimination because she directed or “steered” the couple away from a particular apartment because of their sexual orientation.
Although source of income isn’t a protected class under the FHA, the contention is that excluding recipients of child support, Section 8 vouchers, unemployment benefits, veterans benefits, etc., has a disparate and discriminatory impact on the disabled and people of certain races, national origins, etc., who disproportionately rely on these source