1. We have updated one of the community rules to make it clear that it is not allowed to take higher offers than the given price in a DS-post.
Every now and again, we see sellers state in their posts that their items are "or best offer", then accepting higher price offers than the original selling price they gave. This is not allowed. "Or best offer" can only be less than the given price if the post is labelled "DS". If you wish to get higher offers on your items, please post them as an auction.
You will only be reminded to change your DS into an auction the first few times. But if you ignore this rule regularly in hopes not to get caught and make more money on your items without having to wait for an auction ending, it will result in a warning.
2. It also seems not to be clear to everyone that a BIN (buy it now) price you give in an auction is the maximum price. If someone agrees to pay the BIN, you are not allowed to take offers higher than the BIN. Of course you can refuse to sell to a certain buyer and sell to someone else instead as long as you didn't agree to sell to the first person, but only for the amount of the BIN price.
"Agreeing to sell" is either by telling them that they can have it, that they have won the auction, by asking for their paypal to send them an invoice, or by sending out an invoice.
We hope this will clear up any vagueness about pricing. As always, if you have any questions, concerns or suggestions, please comment or send a message and we'll be happy to explain and take your opinions into account.