Paypal or Alertpay chargebacks, what if the seller has already withdrawn money?

AS per my knowledge there will be the transaction receipt which tells that we have paid the correspondent for so and so. hence we can file a case if the money is not returned and if the product is not delivered hence there are few principles or description which is mentioned in paypal before logging a complain check that it is met. and there seem to be an option where you can with held the money until you receive the product. Thanks Maru don't forget to rate my comment.

Well if there is no money in the account as a seller or a business person doing business and using paypal or Alertpay you need to have a backup funding source so when there is a charge back you have a way of covering it. They are going to get there money. Paypal at least is suppose to put a freeze on your money while they investigate. Where the problem comes is when they use a normal credit card to pay and they call there credit card provider to get a charge back issued. Paypal has no choice but to refund the money's immediately. You can file your stuff with paypal but they cant do anything as your money is all ready refunded, you might have to take them to court. Now on your end you will have a negative balance in your account until you bring the balance back to zero.