You have experimented with Google Cloud using your own credit card and expensed the costs to your company. Your company wants to streamline the billing process and charge the costs of your projects…

Granting a 'Billing Account User' role helps manage the billing account but does not change which billing account a project is linked to, nor does it address the initial problem of transferring costs to the company's invoice.

Setting up BigQuery billing export is for cost analysis and reporting, not for changing the primary billing method or consolidating project billing under a different account.

While Google Billing Support can assist, the primary operational step to change the billing source for projects is a user action within the Cloud Console or via `gcloud` commands, not just opening a support ticket to request an invoice change.

The most direct way to streamline billing and ensure your projects are charged to your company's monthly invoice is to change the billing account for your existing projects from your personal one to your company's established billing account. This ensures all associated costs are aggregated and billed under the company's financial structure.