Did you know that you can suspend a transaction by selecting 'Hold'?

The hold feature is available in transactional documents (receipts, vouchers, slips, and adjustment memos). While a document is on hold, you can create other documents, carry out other activities, or even
exit Retail Pro.

For example, if you begin to ring up a sale for a customer and she has forgotten her checkbook in the car, you can put the receipt on hold while the customer leaves the store. Instead of waiting or losing the data you have entered so far, you can ring up other transactions and then unhold the document when the customer returns.

Holding does not update the document or affect inventory. Holding is workstation specific. You must unhold the document at the workstation it was
created at.