If you use Quickbooks Online to manage your Billing, but wish to use CARET Legal for Practice Management, you can generate bills under the Expenses tab in the Time section then share them to Quickbooks.
When you have linked your Quickbooks Online Account to CARET Legal in your Firm Settings, new invoices will automatically be shared to that account.
Whenever you approve or update an invoice, that invoice will be available in your Quickbooks account.