Metal racks for free! look for a metal bed base cut down the middle with an angle grinder you now have a set of racks capable of holding about 6-8 boards,get some plastic caps from bunnings to cap the ends ,bugle screws or 8mm dyna bolts to fix onto wall- total outlay about ten bucks.Recycle and re-use.
I am sure with a few beers and some long thought you could come up with something. Draw up a little floor plan and what you are after and I am sure between us, builders, tradies, brainiacs etc we can find a solution for you and your loved ones..