It's very common for users to have certain products that they do not stock and instead have a supplier ship for them.  This is commonly referred to as drop shipping.  Another very common practice is "Just In Time Inventory", or inventory that you order AFTER you've sold it.  In order to leverage drop shipping with 0 stock on hand, or just in time inventory, you'll first need to set up supplier quantities.

Set up Reorder Points

First, you'll need to set your reorder points for all of the drop ship products.  This can be done in bulk using a spreadsheet import, or manually one by one.  You'll need to set the reorder point to 0 for the location you're selling from.

Input Supplier Information

Next, you'll need to be sure that you have the supplier entered into each product so you can quickly create a purchase order specific to each supplier.  This step may be optional if you do not source from multiple suppliers or do not want to split orders up based on supplier.

Use the Reorder Function to Create Purchase Orders

Once you've listed based on supplier quantity, you'll start getting orders in Finale that create a negative available quantity.  This is because you have no inventory on hand, but Finale is telling your marketplaces that you do, based on what you input for "Supplier Quantity".  Because you set the reorder points to 0 though, you can quickly create a purchase order for all of the items needed.  Use the reorder function on your home page to generate a PO.  Here, just choose the supplier, and Finale will automatically populate a purchase based off of all items that are below 0 quantity available, satisfying the orders.  

Visit here for help with the reordering PO.

*Note - If you're using the reorder function for your other products as well, it's helpful to either use a category for "drop ship" so you can filter in the reorder screen.