im in the same boat as you. I do tons of work for clubs and DJ's which is just about the easiest thing ever. take the footage drop a track in FCP and edit with some flow. if its like a 2 minute video , i would charge 250. for something around 4-5 I would charge 500$.
Alot of people dont understand how easy it is to make videos. So charge them up if you dont think they can help you out.
As for tiesto I would charge them a cheaper rate because A. youll have a good time B. youll end up making contacts from doing a video for such a major artist and C. very good for your demo reel.
I fucking love the Film Hustle.
http://www.freeonsmash.com/videos/watch/68dmflfbhgdrax79/
45,000 views in less than 24 hours check out your boyyy