There'd be a serious back-out penalty. You'd either have to buy the options back at a fair price, and you'd lose access to the site if you were acting in bad fa

There'd be a serious back-out penalty. You'd either have to buy the options back at a fair price, and you'd lose access to the site if you were acting in bad faith. Yes, people would have the right to refuse work, but if they abused it, they'd lose access to that market. As with any other contract, people who backed out would face penalties as agreed-upon (at the very minimum, repayment of what they earned in the original sale).