My old garden stool works well enough, but its construction is not sturdy enough and the legs are becoming wonky. (Alternative version: its user needs to lose 20 pounds). Today I cut wood. I used the dimensions of the old stool, but added 2 inches to the height, to match my legs better, and two inches to the width for stability. It will have 6" castor wheels, which add 7" to the height, so I subtracted that. Here it is so far. The wood is stuff I found in the shed, mostly a 3/4 inch thick plank, and some 3/4 inch plywood. The supporting members are 2 x 2 bundled for something and stored in the shed. Back view, not assembled. The extra 2x2s are for the top. Front view, not assembled. I see I need to cut a different 2x2 to fit the back more snugly. I want one side open, to hold garden tools. The back is closed to add rigidity. There will be 2x2's for the top, as for the bottom. I think I'll use up my tube of liquid nails as well as deck screws. To decrease the weight a little, I'll cut circular openings in the ends using my handy 4" hole saw. Maybe the back, too, but I should test it on some scrap plywood first. Might splinter too much. It doesn't look like much yet but we are getting there. It will need sanding and I think I'll use deck stain from the garage, plus it gets the casters, a pull rope, and a pad to sit on. More to follow. (oops, I see I posted my original plans already. My apologies for posting this separately).
What I'm now going to suggest, may not apply for you. But if this was something I'd make in my area. I'll put a screen in the 4 inch holes you'll be cutting. Because over here, critters will get into it. Like a lizard, centipedes, spiders, or worse - A snake... Otherwise everything looks fantastic!