Nope, haven't tried doing the storage units, I'd want a sizeable chunk of land with an outbuilding and burn pit as a staging area before jumping into it, as my 20x20 workshop is already cluttered enough currently!
Regarding your domestic situation, I'm in a similar position with my wife being a professor and I being "Mr Mom" watching our baby girl at home. Years ago most of what I sold on eBay was antiques/collectibles, and while the money was good enough I felt that I could build something more efficient and profitable. The problem with "unique" items is that aside from the legwork finding them you need to take fresh pics and write new descriptions for everything as well as safely package the different items, which can take a lot of time. I figured that the best way to improve efficiency was to grow, collect, and purchase bulk materials for me to harvest and process or repackage into small "consumer" quantities, all with standardized packaging, labeling, and shipping methods to sell via dutch auction, which means that for the effort expended making 1 nice antique listing, one could create a dutch auction that stays up for years and sells hundreds or thousands of units. So for example, you could research the most popular heirloom vegetable varieties and start growing them for seeds to sell (if I were in GA I'd be growing buttloads of the ultra-spicy hot pepper varieties for seed to sell, the demand is enormous), go "wildcrafting" for desirable wild herbs, seeds, nuts, fungus (people sell dried morels for gobs, and I made over a grand 1 year just selling giant puffball spores haha), tree burls and whatever else to sell, or find bulk products that are in-demand to repackage (big bags of tannic acid, red iron oxide, polishing compounds, or literally 100,000 other things). That way you have access to a truly global market and won't be constrained by the apparent frugality of your area. I rolled out of bed this morning to see 614.48 in sales today with 2/3 of the day to go, and a theoretically endless supply of those products, with some of the bulk-purchased ones being marked-up over 3,000%. It takes some work and good sense to get-going, but certainly beats fiendishly scrounging around for the next special antique to make a stack off of. If any of that sounds appealing you can PM me for more info, I gots me some pretty decent ideas.