Hello, it is my first build ever and I'm going to purchase my parts from Newegg.ca There are several items that say "20$ Rebate card, or 15$ Rebate card" etc. Well, I don't really understand how those rebate cards work. I will receive these in-mail rebate cards when I purchased the item? So that 15$ rebate card can be used in my NEXT purchase from that brand? Can you explian me more clearly please.