The only way to find out about what they charge would be to ask them...
You can read more about how they determine prices for designs here...
The Go MediaZine - Exclusive insights for art, design, marketing and more. » A Designer’s Guide to Pricing
Maybe someone from Go Media will chime in on here, but my guess is that it all depends on the client and what their needs are.
Their vector packs are awesome...so are their tutorials.