To falsely deny a rental unit is unavailable to some applicants
To advertise in a manner that indicates clear preference based on group characteristics i.e. skin colour, or
To set a more restrictive standard, such as higher income for certain tenants
Refusing to make reasonable accommodation for disabled tenant needs, such as, permission for permitting guide or hearing dogs, including any other service animal.
To set different terms for certain tenants, such as, adoption of an inconsistent policy of responding to late rent payments, or
Of terminating a tenancy for a discriminatory reason.
On that cautionary note, another fair bit of advice, avoid expensive landlord / tenant litigation, by taking necessary precautions, such as, screening tenants and conducting background checks on prospective tenants. A simple click of the mouse and one can visit www.e-renter.com for tenant screening and background check services.