I started loading 9mm about 25 years ago on a Lee single stage with a Lee anniversary kit and loaded many thousands of rounds with it. Very cheap initial investment. About 10 years later I got a Lee Loadmaster kit with a few extra turrets and set them up for 9mm, 38, 357, 40, 308, & 223. I loaded many hundreds of thousands on it and still use it. I was shooting 16k of 9mm per year so my equipment paid for itself in a few months, not to mention the savings from 357, 223, & 308.
If I was starting fresh now I’d get a Lee classic cast turret, 2-3 manuals, a digital caliper, rcbs 505 scale, Lee dies, some MTM plastic ammo boxes, a press light kit, and a log book to keep track of every load you try. Pick up whatever primers are cheapest locally, some BE-86, and some RMR 124 gr bullets and you should be off to a good, inexpensive start. You can(and will) add more stuff later as you decide what you need.
The advantages of loading your own, once you have a stock of supplies, is if there is another shortage you will still be at the range shooting instead of hitting 5 stores looking for overpriced ammo, you can tailor the ammo to your gun, if you want something light for plinking, hot for hunting/defense, or something to get the most accuracy out of your gun. Totally up to you and not hard to do. During the early Obama shortage years I was at the Range whenever I wanted to with full ammo cans of whatever I was shooting and didn’t care how much I shot. Many folks were there with one box and sad faces.
The bottom line is I’d reload regardless of weather I’m saving money or not. I tailor my loads to each gun for accuracy, I load for 6 9mm’s and I want the most accurate, least recoiling, cheapest load for each one. I cast my own too, and powder coat them to keep costs down. With free lead from Craigslist, free brass from the range, all I pay for is powder and primers, so about $45/1000 for 9mm, 38, 357, or 45 is where I’m at. With RMR bullets I’m at about $130/1000. No where does anyone sell ammo that shoots as good as what I load at any cost. I can load anytime I feel like it, and as much as I want. I don’t have to rely on any store to have ammo for me with limits on how much I can get, I just make it when I want, the way I want it.