Old permits had prices based on who knows what - some were pretty reasonable, others not so.
Currently they have an actual formula for figuring out the cost.
Can't recall the exact formula (sorry!) - one price for residential, one for "commercial" (higher). It's a certain amount of money per square foot of deck/dock.
I believe that you will also have to submit a construction plan, map of location, letter of recommendation from Town Board and have a site inspection.
The permits have gotten quite expensive.