Hi Habib,
I am a co-founder of DevOpsBox. I hope you don't mind some self-advertising.
We try to be as cost-effective as possible to be a good fit for startups. For example, we use AWS ECS Fargate instead of Kubernetes, NAT gateways are optional in our setup, and we take advantage of SPOT instances too. Also, we use services with as low operational overhead as possible e.g. RDS or again ECS Fargate instead of Kubernetes.
I know that our website (
https://www.devopsbox.io/) is a little bit outdated, so I would be happy to show you our demo.