Shopify Invoice Printing Integration

I need help adding robust invoice-printing capability to my existing Shopify store. The task is straightforward:

• Identify a suitable printing app that supports clean, professional invoice generation.
• Configure and integrate that app so invoices trigger automatically at checkout and remain editable from the admin.
• Test the flow end-to-end to be sure customers and I both receive the PDF invoice without errors.

I already have the store up and running; I’m just missing this one piece. If you’re comfortable with Shopify app integration and have handled invoice printing before, let’s get this wrapped up quickly and cleanly. PREFER ADELAIDE BASED PERSON FOR ONGING WORK