Once the thing has ended huni and someone has one, it gives you an option to send them an invoice for the item won, so maybe an idea to do this!
Then they should contact you via email or something and advise to how they shall be paying for the item when they are sending it and also to arrange collection etc
Or theres also a option on there for you to Contact Buyer, this gives you the option once you've clicked on it for you to email them

so then you can put in there whatever you want and also perhaps if you want to put your mobile no in there for them to give you a call
hope that helps a lil
xxx