Hi, Can Zoho Books implement TRAINING SALES receipts and push them to eTims for test?

In other words how can we send to Zoho or even create in Zoho training mode invoices and TEST the workflow POS>Zoho Books>eTims and back without actually registering a sale?

How do you implement API connections and requests from a POS to Zoho Books and push remotely to eTims succesfully without testing it first?

(since I understood there is no sandbox for eTims&ZohoBooks API)

Thanks in Advance to the community

Kind Regards

Fred