Enable Buy Now on product listing

I want to be able to add a Buy Now action to the Classifieds Theme products. This would allow users not only to post listings for selling but also but products. Ideally, orders would add up to the order manager or be a hybrid between Shop theme and Classifieds theme.

I thought this was an available feature, but i guess I was wrong, or maybe i purchased the wrong theme… what I wanted was a marketplace sort of..

Thank you!