Overview
We handle layby and eway orders as sales orders with a exiting payment. We also handle back orders for walk in customers that want a product we don't normally stock in the same way. The payment may be partial or may be the full value of the order.
Procedure
Part or full payment for a sale order can be made via the Pay button 
to represent a deposit (20% of the order value) or balance payments on ordered goods or the full percentage. https://readysell.atlassian.net/wiki/pages/viewpage.action?pageId=43483179
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