hi,
based on the tables that we can see in the document settings, we do not have any unit price table in purchase request. the prices that are given in purchase request in normally used as a suggestion for purchasing division on how the prices are. because the one that should know on how the prices are, should be the one who made the purchase order. in would be inefficient if the should edit the prices every time they made a purchasing order document based on purchase request.
if the user who made the purchase request would like to create a Purchase Request then take the pricing through to the Purchase Order to save keying twice, i would kindly suggest to make the document directly from the purchase order, with approval from the purchasing department.
i really hope this would help. Cheers