..... and imagine that as you leave all you eBay sold parcels in your "OUT" box situated by the road km from your house and somebody else but the postie would collect them.  Definitely bad idea, which ever way you look at it.

imagine a PayPal clause that would say something like:

Parcels left in the outbox at your residence for collection by the Postal Service are not covered by PayPal's Seller Protection. 

and then sellers coming to the boards saying "But I took a photo of it in my outbox to prove posting"  :^O

Still a bad idea for posting of eBay items.