Bringing Used Equipment Back Into Inventory
Bring inventory back in using a PO. Add the equipment to the PO using a -1 for the quantity. If this was a leased machine and their is a buyout associated with it that you will have to pay the leasing company for then input the buyout amount as the cost on the PO. If there is no buyout then leave the cost as 0. Once the PO is received it will bring the machine back into inventory at the cost you specified on the PO.
To capture the costs of refurbishing the machine, I would use the Inventory\Production\Refurbish feature in EA. This allows you to add the costs of parts\supplies\labor to the cost of the machine and reduce your inventory for the items used at the same time. Using this feature will give you accurate costs on the sale of the machine.