Sales features are not inbuilt with BuddyPress, but we can allow users to sell items with BuddyPress using WooCommerce and we can display there listing items at their product and can also sync their new items listing with BuddyPress activities. We have offered a similar solution for BuddyPress, you can take a peek here Storemate https://wbcomdesigns.com/downloads/storemate-dokan/
buddypress allow users to post items for sale?
Update on March 17, 2020