I love leaving all my grooming tools, shampoos, spurs, horse boots, etc in a milk crate. They store easily and hold a lot, and have small holes in the bottom so they don't get full of dirt.
For storage instead of some fancy tack trunk I use a Stanley tool trunk. They're a fraction of the price, super durable, and have wheels so they're also great for showing.
For my grooming tools I just put them in a little step stool that opens up (I also use it to stand on to saddle my horse lol) and you can put the saddle cover and boots in there too. Also I have a saddle rack on the fence where the groom box is and that's where the saddle and pads sit. Then the halter and lead is hanging on the stall door. The reins and bridle are on a hook by the saddle. The cleaning supplies are organized by need at the end of the wall:)