"I'm gonna get nailed for this but...private property owners should be allowed to restrict/admit whoever they please onto all or any of their property."
That's all well and good when that property is yours alone and not to share with anyone else (if everyone entering your space is a guest). However, what do you say when there's a Homeowners Association that rents out their property to others? It may be private, but if they're going to rent their property to others, you have to take into account the freedoms of others who may want to rent.
This is why the anti-discrimination act came along - to provide reason to the selection process. In other words, if you want to keep riffraff out, then fine; run a background check on everyone (regardless of their race) applying to rent your space. However, to say that you just don't want someone in your space because he/she is a certain colour is a baseless argument, and it hurts the freedom of the people wishing to rent.
I'm not so sure I follow you but...no one should have the "freedom" to anothers property.
"It may be private, but if they're going to rent their property to others, you have to take into account the freedoms of others who may want to rent."
Unless the potential renters or customers are smokers, then discrimination is OK. In addition, your argument above is the foundation for forcing land lords to rent to people that participate in immoral behavior. For example, imagine forcing a Christian land lord to rent to a Homosexual or forcing them to enter a lease with Planned Parenthood.
"This is why the anti-discrimination act came along - to provide reason to the selection process."
Much more reason would have been applied to the process without government intervention. Yes racism is morally wrong, yes it is harmful to the victims and no it should never be tolerated. However, government intervention has done nothing but create more riffs. The progress made up to this point is more of a result of market needs and individual personal growth.
Take a look at "Applied Economics" by Thomas Sowell for a decent discussion on the topic.