>> What do you house your potting soil etc in??
I save the original bags (1 or 2 cubic feet, heavy-gauge plastic). If I only fill them back up half-full, they stand on their own after I thump them up and down a few times to settle them and spread the base a bit.
It also helps them "stand up" when I have several in a row supporitng each other, or if they can lean against a wall.
The top half folds over and keeps dust out, and maybe keeps the mix moist a little longer.
I can get a small shovel in FAIRLY easily if I roll the tops down part way. Or I scoop mix out using a laundry detergent jug with the bottom cut off and the cap screwed on. Once the bag is only 1/3rd or 1/4 full, I can lift it easily and pour it out into pots or a wheelbarrow.
A wheelbarrow with heavy-duty steel shelving over it makes a kind of a potting bench, though usually with a slope.