[SCOTI]

Agreed. Communication from both parties is needed during a transaction. Some suggestions.....

Sellers:
Be as accurate as possible on description of items.
Include your intended shipping options & your ZIP code.
Have the item/s ready to ship.
Have an idea of shipping costs when posting items for sale.
Acknowledge when payment is received.
Communicate when items are shipped.
Forward any/all tracking/shipping info.

Buyers:
Ask specific questions if necessary.
Be prepared to pay ASAP. Communicate a timeline for payment.
If a seller indicates 'plus shipping', do the legwork on shipping costs vs. just leaving the burden on the seller.
Communicate when payment is sent.
Acknowledge when items are received.