So I would think this is quite straightforward, but it's turning out to be a bit more complicated than I expected.  

What I am looking for is to simply have Parent and Child Products.  For example the parent product/item is a car and the child product/item are the tires, engine, etc...

I would like to be able to add a Parent product (car) to the estimate/sales order/invoice and then have the child products (tires, engine, etc..) show on the purchase order.

I was assuming that composite products could be used for that, but the purchase order still only show the parent product (car).

Is this something that can be accomplished.  We sell trade show display booths that sometimes have 20 or 30 line items that need to appear on a purchase order and it would be impossible to manually add them every time.

Thanks in advance for your help.