I know what you mean. My father inlaw gave me his wheel horse tiller I use for cultivating and I'm pretty sure some china man is missing some fingures how deep it goes.
When my wife and I 1st bought our hobby farm we used what we had at the moment for our 50x50 garden. I used my 700cc atv with a spring tooth drag. It worked really nice in the spring but would plug up sometimes with corn stalks in the next spring. It dug deep though.
After I had some extra money I bought a small disk. I really liked it it chopped up the residue really well. I had to make multiple passes to get a nice bed. It really compacted the soil though and I started to lose production.
I'm into restoring antique tractors and implements and playing farmer.
I bought a fence line plow for 100.00. That really turned the soil, buried residue, got rid of the hard pan and up production.
I also bought a field cultivator for 100.00 and pull a drag behind it. It just kind of scratches the grand vs the spring tooth I had.
I also have a tiller for the Kubota. It leaves a nice seed bed, but struggles with thick reduce.
I was in the same boat as you. I wanted a brush hog but would only use it once maybe twice a year same with a post hole auger. You can find cheaper......and maybe more solid units at auctions, or on 3rd party sale sites. The only thing is some older equipment doesn't hook up well to newer quick hitches.
If I only had to have 1 tool I'd probably get a disk. There's a whole bunch of videos on disk and tiller debates online.