A few hundred on reason and rebirth, a few hundred on ableton live and upgrades over the years, maybe 300 on NI Traktor, that’s it. Maybe 1500€ in total over 25 years.
Definitely less than the 20k on Hardware 
but that always works. Software… as long as it lasts.
Just Ableton Live 11 Suite - £275 thanks to the Polish reseller (no intention of upgrading any time soon)
Oh and Arturia Acid V - £57
It’s a fair bit for me as I do a lot ITB.
I do question it at times with all the updates and whatnot, plus the fact that eventually that SW can be as bricked as hardware. But then again, I’ve had 3 years at this so far, and if I can get plenty of juice out of these over the next 5 or so, I won’t be complaining. For the most part it’s been a useful and fun experiement. I have my go-to stuff, my once-in-a-while things, and a few dusty gems that come out once in a while. Most of it plays a role at some point. I notice that there are some plugins today that have had a lifecycle of 10 years, so as of the minute I think I’ll get good value for what I’ve paid.
I’ve been able to offload quite a bit of what I don’t use, which is good because it’s a low risk way to try things out in your productions. I may sell even more. But one thing I would change if I went back would be to not buy anything with NFR from the outset. That means no Output stuff, since you can’t sell those outside the EU. Nor Baby Audio where you can sell, but it costs so much that it’s not worth it. Props to NI, Arturia and others who allow generally pain-free (and actually free) transfers. There are loads of good companies who don’t rinse customers. They charge a fair fee and then maintain the software for a long time, which is about as good as you can hope for.
Feels like I’ve reached the outer reaches of exploration at this point, and now just hunkering down with those picks to see what sticks. The plan now is to basically let it sit there, upgrade only the absolute cream of the crop - and chalk the duds up to experience.
Somewhere between 5 - 10.000$ 
$200 for Logic Pro, and <$100 total for various iOS apps. I’ve gotten about 8 years of use out of all that so far, and am nowhere near to exhausting the possibilities.
The amount will increase soon, as I’m planning to get Ableton Live in order to facilitate performances.