This has been proposed multiple times in the past, and for some reason never gotten enough votes, but having to purchase each item individually is a sure fire way to lose business. Both from a marketing and customer service standpoint. People are likely to buy more items if they don't have to purchase everything individually, and as customers we can get impatient and sometimes change our mind. so we like to have the ability to put things to the side and hold on to them while we shop then decide at the end what we will be purchasing. If I'm forced to buy individually I get frustrated and get out of the store as quickly as possible, which gives you less money. You want your customer staying and browsing for longer, as they will find more they want, and will be happier to buy more. There is also the security issue with having to purchase multiple items from one site individually. My bank sends suspicious activity alerts when it gets frequent purchases from the same establishments and it will occasionally shut the card off until it verifies the transactions are authorized. The interruption in the flow of purchase can make a customer frustrated which can lead to lower sales. Just think about the last time you had to deal with your bank's customer service. Even if it went smoothly it still took time out of your day. How likely would you be to spend money at the website when you knew that would happen every time? So for both customer satisfaction, and your own financial reasons, you really should implement a shopping cart feature into your marketplace.
