Pre-Writing Your Teardown Script: The Discipline That Saves Your Bill

The pattern that's saved me hundreds of dollars in lab spend isn't a fancier cost dashboard. It's a rule:

Write the teardown script before the create script.

If you can't articulate how to delete the thing, you don't get to create it. This sounds austere. It's actually liberating — because you stop half-trusting yourself to "remember to clean up tomorrow."

Three rules

1. Every lab gets its own resource group. rg-lab-... prefix. Never mix lab resources with permanent ones.
2. Every lab has a scripts/lab-teardown.ps1 that takes the RG names as a parameter and supports -WhatIf.
3. Every lab session ends with running the teardown script before you close the laptop.

Skeleton

[CmdletBinding(SupportsShouldProcess=$true)]
param(
    [string[]]$LabResourceGroups = @("rg-lab-dev-swc-001")
)

foreach ($rg in $LabResourceGroups) {
    if ($PSCmdlet.ShouldProcess($rg, "Delete RG and all contents")) {
        # Purge soft-deleted Key Vaults so they don't block recreation
        $kvs = az keyvault list -g $rg --query "[].name" -o tsv 2>$null
        foreach ($k in $kvs) {
            az keyvault delete -n $k -g $rg
            az keyvault purge -n $k 2>$null
        }
        az group delete --name $rg --yes --no-wait
    }
}

The Sunday checklist

Tape this to the side of the monitor:

• [ ] ./lab-teardown.ps1 -WhatIf (read every line)
• [ ] ./lab-teardown.ps1 (run for real)
• [ ] Wait 10 minutes
• [ ] az group list --query "[?contains(name,'lab')].name" returns empty
• [ ] Cost dashboard back to baseline

The discipline is its own reward. The next morning's bill confirms it.