"By the way, I wouldn't register a domain name that has Realtor in it."

NAR says you CAN use Realtor in your domain name, as long as it's being used to describe you. Like RealtorGreg.com, or GregtheRealtor.com. You must use your name with it... I actually have an email from them because I used it incorrectly, and they promptly sent me the rules and regs for it... so I know them. I can forward these rules to anyone that wants them... email me a request.

"multiple domains pointing to the main site but if done incorrectly, this can cause your sites search engine rankings to suffer"

Not if you don't promote both on the web. Pick ONE to submit to search engines and post in forums. Only use the other in your print material and the search engine will never ever know about it. Even if it does get picked up by the search engines for some reason, it won't hurt anything... you'll actually see the "cached" paged is from the "real" domaim even though you typed in the alias.