Here is a link to a video of Service King Collision Repair Center discussing PDR.
http://www.collisionblast.com/2011/0...s-to-consider/ However, looking at the dent, pdr may not work, as it is in the body line, which would make it difficult for pdr.
As far as the cost for the dent, this does not sound out of range. This is going to depend on the labor rate of the area you live. This could range anywhere from $40 to $100 per hour. Where I live the labor rate ranges from $45 to $55, but again, this could be quite a bit different. With the dent being in the body line, it will make it more difficult to repair. Just looking at the photo, I would guess 4 to 5 hours of labor. A quick guess of 3.0 hours paint time, .8 clear coat. There may also need to be blend time of 1.5 hours. That is roughly 6.8 refinish time. If the labor rate is $50 the body rate would be (4x50) $200. The refinish labor (7x50) 350 and roughly $200 for materials. This comes to $750. Hazmat waste charges, cover car, sand and block, could easily take this over the amount you stated.
It is hard to tell from a photo, and I did not look in an estimating system to get actual times, but just a ballpark, the estimate sounds legitimate to me.
It never hurts to get other estimates. Just make sure that you use a quality shop. You may also ask about pdr, as it may work for the dent. I am not a pdr expert, but it does not look like it would work well for that specific dent.
I have some tips for you when selecting a repair shop to help you make a wise decision.
http://www.collisionblast.com/2011/0...n-repair-shop/
I hope this helps and I will you luck with finding the right repair shop to help you with your damage.