We send out estimates all the time, the customer places an order for the products from us after recieving that estimate, we then convert the "estimate" into "invoice - Draft", It has to be draft because we have not made and delivered the parts yet. When the customer sends us the order, they have given us a "requested delivery date". We are a components manufacturer, so the customer tells us when they need the order by". If we could have a field on the invoice "Req Delivery Date" and this date is available in the "Main Draft Invoice List", then us as the supplier could look at the list of draft invoices, which is a reflection or orders present that need to be worked on / fulfilled, if we could sort that draft list of invoice into "required Delivery Date" and sort the draft invoices by "Required Delivery Date". We could then work through the list of draft orders, in their order of urgency. When the order has been made, deliverd and fulfilled, we can then send the invoice, which then takes that job from the draft list, efectivly archiving it from the job list (drafts). Basically we are using the Draft Invoices list as a current order work sheet if we could sort the Draft Invoices list by required delivery date