Just a bit more info on free services - when we were starting out AWS were offering $10k credits a year for 2 years or $100k credits for one year. I believe we got access to this through one of our investors, but most VCs and incubator programs will be able to do this.
For that I got a Delaware C-Corp, an SVB bank account, and $5k of AWS credits that expired after 12 months. Our AWS bill in that first 12 months was roughly $5k.