The market's bucket is live. Ask Cost Explorer what it has cost this month, in total and by service:
sh
aws ce get-cost-and-usage --time-period Start=$(date +%Y-%m-01),End=$(date -d tomorrow +%F) --granularity MONTHLY --metrics UnblendedCost
aws ce get-cost-and-usage --time-period Start=$(date +%Y-%m-01),End=$(date -d tomorrow +%F) --granularity MONTHLY --metrics UnblendedCost --group-by Type=DIMENSION,Key=SERVICETwo JSON files are waiting in your home directory: budget.json and alert.json. Read them, then create the budget and describe it.