I have been on a few shopping sprees... usually they are around $200-$300. I don't think I've ever spent more than $500 at once (without planning for it, like a new phone) -- but as a poor college student that is a crazy amount for me!!
But usually instead of big shopping sprees, I spend a lot of money spread out over the whole hypomanic episode... I'm an impulsive shopper so I buy things as soon as I see them, I spend $20 there and $15 there and by the end of the episode it adds up to... I don't even want to think about it!