title: How to add quantity based product prices in Prestashop with addon price?
body: <p>How do we enter prices for below</p>
  
  <p>1 Banner  = Base price $20 + Artwork $5 = $25<br />
    2 Banners = Base price $20 x 2 ($40) + Artwork $5 = $45<br />
    3 Banners = Base price $20 x 3 ($60) + Artwork $5 = $65</p>
  
  <p>Currently Prestashop does not allow to have a fixed addon price for artwork variable. <br />
    It should not get multiplied when the quantity increases. (Artwork is a fixed cost)</p>
  
  <p>How can i do that?</p>