Your code doesn't need to follow the same template, though it could. There is actually added value if there are different algorithms competing to trade toward the peg.

I'd vote for a small user, as long as the amount at risk isn't very large. My vote alone isn't enough but it is pretty large.

As for server, I don't know what sort of creative ways there might be to minimize that cost. In principle, you could run it at home if you have a system you can leave on, so the cost would be just power and (minimal) bandwidth. It might occasionally fail if your personal ISP isn't that reliable (but many are), but some occasional downtime isn't that big a deal for this.