Quotation Price

I have created a Purchase Requisition, and from Auto Create SCreen, i have created an RFQ(Bid RFQ), and using a "copy document" feature i hv created a Quotation.

In the quotation, there are two places for price, one at quotation line level, and the other is at quotation line shipment level, but for a quotation i want to enter the quotation given by the supplier.

My questions are:

1) Do i need to update the price at both shippment and quotation line?

2) If i create a purchase order, which price will be considered for PO?

Appreciate your help on this!!!