The Civil Rights Act, IMO, was legislation that didn't need to be written. All our gov't had to do was point at the Declaration of Independece where it says "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness." and tell the offending states to abide by it or pay a penalty. In addition, I believe the problem would have eventually worked itself out. At that point, black people had already defended the country when they were told they weren't capable. Jesse Owens had smoked everyone at the Olympics in front of Hitler. Many prominent blacks, especially athletes, were showing that black people could and should have a equal seat at the table. I honestly believe that our culture would have changed, albeit more slowly, but in a more honest and transformative manner that would have been better for the country in the long run.
As far as the real estate thing, I believe the free market would take care of these kinds of discrimination. If a real estate agency doesn't want to provide the opportunity to housing, another one will and make more money doing it. Eventually, the discriminating agency will either A) Have to change their policy or B) Be outperformed by and possibly put out of business by the non-discriminating agency.