Gonna need a shed

One of the finer points of home ownership (particularly when you have children) is trying to deal with the accumulation of stuff.

Stuff is expensive, it requires maintenance and most annoyingly it takes up space.   Hobbies and activities all have accompanying needs for stuff.  That stuff eats up every open spot in your home until...you're gonna need a shed.   My property already has a shed, unfortunately it's hanging precariously on stilts as the people that built the shed didn't really consider drainage and nearly 1/5 of the ground under it has washed away.  In the Pacific Northwest watershed management is pretty much what owning property is about.  I live on a hill (are there any actual flat spots in the PNW that aren't in a flood plain?) and the shed is at the bottom of a driveway, the paved driveway acts as a natural river to push the sometimes alarming rainfall right under the shed. I mitigated the worst of the water issues by damning the water from going under the shed, and chiseled a notch in the retaining wall lip that was preventing the water from continuing on down the hill, but I'm stuck with a shed that I want to tear down to repair the washed out section and put in a proper retaining wall with appropriate drainage installed.

The shed is full. Pretty much as full as it can be. Full of stuff, and it's going to take time to tear down the shed, fix the wall and rebuild it, which means that stuff has to come out of the shed and be somewhere. My house sits on about .38 acre so I have some footprint to play with and I have a spot picked out for an auxiliary shed so I've been busily playing with shed design ideas.  The current shed is a 10x12 which according to the planning laws I can find on my cities website is the largest you can make without a permit.  I've read it several times and there's language about how close to property lines it can be, but nothing that says you cannot have more than one. The space I'm looking at isn't large enough for a that, so I'm playing with either an 8x10 or 8x8, the biggest factor at the moment is cost. 10' 4x4's seem to be about double the cost of 8' ones.  I could try to do it on the cheap and use 2x6's, but I'm just not sure that's the route to go.