Close all your auctions before you get bids. If you already have bidders, you will have to cancel the bids before closing or be required to sell to the current high bidder.
Close all your Fixed Price listings as pierre suggests, but I usually don't worry until about 48 hours before.
Your closed listings will stay in your Unsold for 60 days or more, so they will be easy to reopen.
Yes, you will pay again when you relist. Better than getting negs though.