The unit price shown as below in quotation, did you missed anything or install custom module? 

Hi Elly,

Purchase price is like product cost price, and for sales you can define sale price.

First thing: Is the check box Can be Purchased ticked on the product? If yes, the you would see a Purchase tab on the product where you can see Vendors and associated price.

Hmm unfortunately it doesn't work that way.

But I keep on trying to find the answer.