Hello Cody and Welcome.
Without knowing all of what you intend to build and what your future tool needs might be, keep in mind my reply is limited to the known facts.
If you don’t envision yourself building a shed or doing any major home renovations yourself- I think the 12v platform will suit your needs and price points well. I notice in your title that you specifically state ‘Home Depot’. Are you locked into HD or would you consider other stores?
As for manufacturers, Milwaukee has a pretty extensive selection of 12v tools. Drill/Drivers, jigsaw, flashlights, impact wrenches and ratchets, a speaker/radio, multi tool, recip, circular and bandsaws, stapler and much more. In fact typing ‘12v’ into the HD app; there are 227 tool listings for Milwaukee. I am not personally on the Milwaukee platform- however they have received a ton of positive press lately for quality, selection, price and more. Keep in mind the 12v Milwaukee battery platform- has tools that use a slide pack battery and others that use a (hope this is a proper description) plug in/clip in pack that goes into the tool handle. Generally those tools have beefier handles which some people dislike. I do believe that regardless of the battery style- but try and confirm this- all 12v Milwaukee tools can be used with the style of battery, however not the battery size; e.g. the 1ah battery isn’t for use with the 12v circular saw. Milwaukee does make a 12v rivet gun- which may or may not be of importance to you. Makita also makes one but it’s on the 18v platform and costs more than $1,000.
Speaking of Makita, I am on the Makita platforms (12 and 18v) and have been very happy with both (other than vacuum hose diameters and finding OEM accessories at times; both of which are less important on the 12v platform). On the 12v platform Makita offers many of the same type of tools as Milwaukee; including: drill/drivers, circular, jig and recip saws, flashlights, impact drivers, wrenches and ratchets, multi tool. They also have two tools that I don’t believe Milwaukee offers: a 12v rotary hammer and a 12v tile saw. As for performance, I have had great results with Makita. The batteries last (duration and longevity), charge quickly and have all the usual bells and whistles of circuit protection, etc. It certainly has to be stated that all Makita 12v tools use a single slide pack style battery type. They don’t have the range of power options (2ah and 4ah) as does Milwaukee; but I’m not sure that’s really all that applicable to your needs. On the downside, Makita is harder to come by (more prominent overseas) than Milwaukee. Makita can be more expensive as well. Also absent on the Makita platform is a cordless wet/dry vacuum. Makita does make a nice stick vacuum, but missed an opportunity there which Milwaukee fills nicely. One incredibly annoying thing with the Makita 12v platform is they took the 18v compact recip saw and slapped in 12v electronics. It isn’t a smaller form factor (as I need to fit into a tight space) or design- its the same saw! Opportunity lost. They didn’t do that with any other tools that I know of.
One great benefit to these OEM’s is that Milwaukee and Makita (and Dewalt) all make dual chargers that can charge both 12v and 18v batteries at the same time- in the event you like these platforms but find you need a little more power for a tool or two and buy into the 18v lineup down the road.
As for Ryobi, Ryobi gets a bad wrap. I’ve seen them in almost every contractors tool arsenal. While you are limited to 18v; ergonomically they aren’t as friendly as other brands and their battery packs are gigantic- but they make a huge variety of tools. All battery work in all tools and if used properly and not pushed beyond their design will get the job done.
Above I noted Dewalt dual 12v/18v charger. I haven’t commented on Dewalts 12v tool lineup. It isn’t as expansive as Milwaukee or Makita-it almost appears as Dewalt may have abandoned it. Definitely they’ve focused on the Flex and Atomic series tools more than 12v Max lately. I’d probably stay away until they at least bring a 12v max circular saw to market.
My final input; there are good return policies at most retailers. I’m not advocating that you buy a tool and once your project is complete you return it- but if you buy one or two tools, try them (be sure to save the packaging and all materials) you can return the tools if not satisfied. It’s almost, almost risk free.
Please let us know what you decide and how it works for you and your projects.