The folks at the travel website Kayak say they've figured out the best times to book hotel rooms, for the best deals.

If you're going to Las Vegas, prices start to fall within 30 days of check-in. So, if you're heading to Sin City, don't book that hotel room too soon. As Kenny Rogers sang in "The Gambler", you have to know when to hold up! Book sometime the month before your stay.

It's a different story for New York City. Kayak says you'll find the cheapest rates the week before check-in. If you're heading to the Windy City, it seems pre-planning really pays off. Kayak says you can get the best deals in Chicago (nearly 30 percent) by booking four to five MONTHS in advance.

And, for Orlando, one of the most popular destinations, the website says you should book no earlier than three months before check-in.

Of course, these are the conclusions from one travel website. You might check with your own travel professional to see if the advice matches up.

Then, give these tips a try and you just might have some extra spending money for your next vacation!