How much might #Nosflare cost you to run? By default, Cloudflare Workers and D1 database is free! However, I recommend upgrading to the paid Workers plan of $5 USD per month.
If the relay doesn't get insane amounts of traffic, you may only end up paying just 5 bucks to run it. Or, if things grow rapidly, checkout how cheap things cost at scale:
Workers:

Cloudflare Docs
Pricing
Workers plans and pricing information.
D1 database:

Cloudflare Docs
Pricing
D1 bills based on:
As you can see, it is incredibly cost-effective to run a #Nosflare-powered relay instead of another relay implementation with traditional VPS, as Nosflare has instant scalability vertically and horizontally. None of the headaches with Nosflare you would normally have with spinning up a webserver, configuring it, hardening it, monitoring its finite CPU/RAM, failure due to maxed CPU or OOM errors, susceptibility to DDoS and other attacks, etc.

GitHub
GitHub - Spl0itable/nosflare: A serverless Nostr relay through Cloudflare Workers and Durable Objects
A serverless Nostr relay through Cloudflare Workers and Durable Objects - Spl0itable/nosflare