But an estimate? the cheapest amount?

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I would rather be lost in a book than reality.

I know you just want an estimate, but your best bet is to go on something like travelocity or priceline, and it will show you options, and allow you to play around and try different dates and airports to figure out what would work out the cheapest for you.

The cheapest there was 323.  But then again, those are using random airports, and that can make all the difference (Texas is a big state... so where you land can make a difference...)  This one's Norfolk to Dallas/Fort Worth.  If you play around with it a bit, you might pull out something cheaper... btw, if you by it less than 2 weeks in advance, you will see a HUGE price increase.  So buy it as early as possible... The link is for the end of August.

If I change it to the end of July, the minimum becomes 475.