Short version: An Application or Network Load Balancer costs ~$0.0225/hour - about $16/month - just to exist, plus capacity units. Classic Load Balancers run ~$18/month. Load balancers outlive the services behind them: the app gets torn down, the ALB keeps billing. Here is how to find load balancers with no real traffic or no healthy targets, and remove them safely.
Short version: Every NAT Gateway costs $0.045/hour, about $32/month, before a single byte of data, plus $0.045 per GB processed. They are easy to create per subnet and easy to forget. Here is how to find NAT Gateways that carry little or no traffic, delete them without breaking egress, and stop paying NAT data charges for traffic that could use free VPC endpoints instead.
Short version: Since February 2024, AWS charges $0.005/hour for every public IPv4 address, about $3.60/month each, whether it is attached to anything or not. An unattached Elastic IP (EIP) is pure waste, and orphaned network interfaces (ENIs) often hold them. Individually small; at scale, and multiplied across accounts, it adds up. Here is how to find and release them safely.