How can I print receipt for invoice paid by client

Printing receipts for a client proof of payment is a breeze, @userdarren1.

To get started, simply go to the All Sales window. Let me guide you on how:

1. Go to the Sales tab and click All Sales.
2. Look for the Payment transaction for the specific customer.
3. Click it to open.
4. Then, select the Print button.

Then, to further assist you in receiving and processing your customer's payment, here is the article you can read: Record invoice payments in QuickBooks Online.

Also, monitoring your sales and customer transactions is easy with QuickBooks. This is more possible because the program has ready-made customer reports. To access them, simply go to the Reports menu and scroll down to the Who owes you section. From there, select any reports you'd like to open. 

Feel free to post here anytime you have concerns about printing receipts for your clients. I will be happy to assist you. Have a good one