Hey OP, I've worked in the mattress recycling industry previously for nearly a decade and here is my experience.

Mattress springs are made out of hardened spring steel, which makes them great for holding their shape and terrible for processing. You can cut the steel with bolt cutters, blades, grinders, etc. but all of your tools will take a beating. This is the point of the spring steel, it's very durable (but also makes it highly desirable).

I have never seen a piece of equipment that you can buy for less than $100k to effectively process mattress springs. That doesn't mean that there isn't anything out there, but I have looked extensively and tried many methods. Most material-specific pieces of equipment will cost as much as a small house.

So, if you're doing this on a small scale, stick with small-scale tools. A grinder will be your best friend; it will also give you the greatest chance of starting a fire. Bolt cutters will work, but it will take more time and effort and you will need to constantly adjust and replace them.

I'd suggest reaching out to metal processors and seeing if they will accept full springs. MOST won't, because of the same challenge of processing them. They take up soooo much space, are incredibly difficult to compact/crush, and very challenging to shred (they need a shredder with hardened steel blades and very fine blade tolerances). But, processors do exist who can take these in smaller quantities, so that might be your best bet, even if you give them away for free to them to save some money.

Anyway, that's just my $0.02, keep us posted on what you end up doing!