Onboarding and risk management tools for financial firms. Monthly spend is about $1500, which is about 10% of revenue. I can probably spend some time and bring that spend down to $1000 with some work (but currently time is better spent getting revenue up)

Edit: I would like to add that with a combination of fly.io and digital ocean the actual server costs are way under $100. Most of the costs are paying for other Saas needed for the product (document analysis, emails etc) and tools (github, copilot, sentry, etc)