The Global Gaming Expo (G2E) will bring just as many attendees as NAR, so for just the two conventions alone there will be 50,000 attendees. Forget all of the other little conferences! Room Inventory is only around 133,000 right now.
I did recommend to Fred to google "Vacation Rentals Las Vegas" and gather a group of friends if you are looking for a less expensive alternative. Also, when searching hotels in Las Vegas, don't forget Henderson! Green Valley Ranch is about a 30 minute drive down the freeway. Going the other direction (west) the JW Marriott (pictured left) is a gorgeous property and the Suncoast is right next door and in great proximity to MANY great golf courses, if you were planning to do something silly like that. I hate golfing, can you tell?
Many off strip properties have free or low cost transportation to strip areas or the convention center. Please make sure you look it up or call them and ask about transportation and drop off points/times.
Just be warned: the days of inexpensive buffets and cheap entertainment are GONE. So if you are on a Realtor diet, be prepared. Fred's wife didn't get the memo :) Maybe you can just crash some of G2E's awesome parties MUhahahahaha! (just kidding!)