The most I have spent on a fish to date is $90, a maculosus angel, and it was very worth it. Sorry, no pics, because my photography skills do not do it justice.
I paid $70 for a 4" hippo tang.
also paid $50 for a flame angel that went carpet surfing a month ago. that's the most I ever lost on a fish.
both of these fish were well worth the price. I wish I'd had a freaking eggcrate on the top.