Ask HN: Feedback on public cloud cost savings tool

It seems that every company on any public cloud nowadays care a lot about cost and how to reduce cloud spend and so I was thinking:

An automated scanning tool where you input an AWS read-only SA and then it scans your infra for potential cost optimizations, and the pricing would be 10% of the potential savings identified and if the tool could not identify any savings, you pay nothing, therefore a potentially risk free attempt.

Any feedback/thoughts would be appreciated!

Thanks