If you can make time to travel, you should try being flexible about the specific dates of your vacation. A margin of just two or three days may be able to save you hundreds of dollars, which is a sweet deal if you ask us. There's absolutely no reason not to be flexible with your dates if you can do it without ruining your travel plans.
If you're already asking for time off work, why not wait to see which dates are the cheapest before making that request?