Serverless soultions is can be incredibly cheap due to their event-based nature - if your system isn't working, you pay barely anything for it. But if you're not careful, serverless can still result in some nasty surprises when it comes to costs.
billing
A collection of 2 posts
AWS Reserved Instances Cheatsheet
Reserved Instances (RIs) are a great way to save some money if you've got consistent AWS EC2 usage, without needing to make changes to your instances!