Selling cards
 

Ok. So we can sell items. I have a HALFLING card.
It says. 'You may sell one item each turn for double price. Huh?
So who decides what the price is? And why would anyone want to pay 'double' the price for anything? Wouldnt they just decline all the time? Doesnt that make this card truly suck? As far as i can tell the onlytime we roll the dice is to 'run away?'

Re: Selling cards
 

Item is a special keyword in Munchkin; "Items" have gold piece values printed on them. That value can be "0" or "No Value", but they will have a value printed.

When you sell an item, it goes to the discard pile; For every 1,000 gold pieces worth of items you sell at the same time (rounded down to the previous 1,000...1,999 gold pieces is still only a single level), you go up a level. Once per turn, a Halfling may sell a single item for twice its listed value...fairly powerful, if you happen to be drawing [or acquiring via "Charity"] a bunch of expensive stuff you can't use.

When items are exchanged between players, that's "trading", and is something else entirely.

The other Halfling ability, unless the printed text has changed (I don't have one in front of me), allows you to try to Run Away a second time if the first time fails, but only if you're able to (and do) discard a card.

There are other times you may have to roll the die...such as a Bad Stuff that causes you to lose a die's worth of levels, or a Curse that costs you a die's worth of items...but Running Away is the most common reason.

Re: Selling cards
 

The key piece missing from this discussion is that some Treasures have a price in Gold Pieces at the bottom of the card. That's the price that the Halfling can double when selling Items for a level.

You can read more about selling Items in the game rules, and if you still have questions, please post a followup here and we'll try to answer it for you.