This is one way to do the core thing, there are probably other ways to do it. I’ve assumed only one item that has a core charge, obviously if you have more than one item, the core charge and core item will have to be specific, you will have more than one of each in other words.
(i.e. core-alternator, core-starter, core-injector)
A core charge is when you are required to get the used item back so it can be rebuilt. Like a starter motor for a car, you buy a new one, but it is actually a rebuilt core you are buying, so the shop charges you a core charge, if you bring back the core, you get that charge refunded.
So you need to charge for the core at the time of sale, and the customer will do one of three things:
Condition 1. Pay the core charge at the time of purchase
Condition 2. Have the core to turn in at the time of purchase
Condition 3. Bring in the core some time after the purchase.
Obviously we need a charge item, an income item, an inventory item, and an account to track core charges and refunds.
Set up an income account called core.
Set up an other charge item called core-charge and select the income account core, enter the amount of the core charge.
Set up an inventory item called core-item select the income account core and set the price as the same as the core charge.
Condition 1. Create the invoice, enter the part being purchased and then the core charge - receive payment.
Condition 2. Create the invoice, enter the part being purchased, and then the core charge, then enter the core-item and a quantity of -1 (negative one), the core-item should have the same price as the core charge. (if you get a warning about not having enough to sell, ignore it)
Condition 3. Condition one has already happened (the core charge was paid in advance). Bring up Create Credit Memo/Refunds, select the customer, then enter the item core-item, a quantity of one (positive one for this action), and the amount, click save and close. QB asks if you want to refund or carry a credit. If you refund, the screen comes up, Select the account and type of refund, click close.
Behind the scenes:
When you charge for a core, the amount goes to the income account for cores. When the core is returned, the inventory item “core-item” increases the amount on hand, the negative amount is sent to the core income account and zeros out the core charge that was posted there. If a refund is issued, the refund is credited to the core income account, again zeroing out the amount received. Since the inventory item “core-item” has no cost, there is a zero entry in COGS.
Inventory increases the number of cores on hand even though you entered a negative one on the invoice (I have no idea don’t ask), so you can see how many cores you have and send them off to be rebuilt when you have enough.