Boat Dock Bumpers

How much would it cost to build your own boat dock with 8 slips?
Just moved into a little lake community where the boat dock is pretty shoddy and there is talk about it needing to be replaced completely. I think we can rally several families to do the work (as it doesn’t appear to be rocket science) and purchase a DIY kit. probably 30-40 out with 8 slips (4 on each side). Neighbors said that the houses with their own private docks paid around $19K for just their one – it has aluminum and is a little fanicier. we just think wood is fine = probably put trex on top for walking on though. We would want some type of bumper or rubber guardon sides too. Any help or info on this would be helpful. Located in ID.
AT LEAST a hundred-thousand dollars. Docks aren’t cheap, no matter what the size and how many slips.
Boat Dock Bumpers that Float!