I have been selling a few things on ebay recently. I haven't had any problems with people so far. People tend to pay very quickly- Paypal has made that very easy. And when I buy something I always pay instantaneously- through Paypal. I am proud of my 100% positive rating. But recently I sold an item and the person who bought it hasn't paid, or even replied to an email. So what I want to know is. ...
1) How long is a worrying amount of time to wait without a payment being made
2) How many polite reminding emails can I send before I appear pushy?

I only want to know because this item has a time restriction and if they don't pay I am running out of time to resell it.