Hello, firstly, welcome to eBay selling and I hope that you have an incredible journey.

OK, Down to business, as a seller, you cannot leave bad feedback, even if they are the most horrible buyers in the world. Additionally, leaving a negative comment with a positive dot, will likely see the comment removed and you to receive a reprimand.

In theiry, you can allow a buyer as long as you like to make payment, however eBay Australia allows a buyer a minimum of 8 days. Let me expand a little there.

You may request payment in 2 days in your terms and conditions, however eBay will not allow you to open up an Unpaid Item claim until exactly 4 days have passed since the time of purchase. They then give the buyer a further 4 days to make payment.

If payment is made in that time via PayPal, the case is automatically closed on your behalf, I'm not sure if this also occurs automatically if you mark the item as paid should the buyer deposit the money into your bank account, you may have to manually close the case yourself in that instance.

You cannot relist the item to resell whilst the unpaid item dispute is in progress, because if the buyer does pay, you are then obligated to follow through with the transaction by posting the item.

If those 8 days pass and you have not received payment, the case will automatically be closed and you will receive a refund on your FVF's (Final Value Fees).

IMO, I wouldn't bombard the buyer with frequent reminders to pay, they tend to get a bit narky when you do that. I believe that eBay does do this on your behalf at least once, so perhaps one other time from yourself would be OK? But that is up to you, but just remember to ask them in a way that doesn't seem demanding. Regardless of how many reminders you send, the buyer will pay when they are ready to, and they may not even check their computers every day to see your messages.

Best of luck with it all.