Conversations allow you to get instant customer service for any of your queries, be it stock or account management.
Offers seen in the Offers tab are specials that are only given to you.So make sure to make the most out of it.
Purchase Lists allow you to organise your Purchase Lists
To bulk order: Go to My Account->Bulk Order, you can add products by name or by SKU numbers. There is an image demonstration below. You can save the list, which will then appear in your Purchase Lists tab.
Subaccounts allow a company to have many accounts, these accounts are all allowed to purchase products at the same discounted prices. To access this function you should go to my Account->Subaccounts