Could these be cut in half or what is the most economical way to get about 100 flat kraft cards that are about 4 x 6?

We would recommend purchasing a Kraft Card Stock and adding a cut to it, or purchase a pre-cut 4x6 card

I have bought similar Kraft cards from other providers and the paper is not very flat, almost warped or curled and will not work in my printer. Is this paper very flat? Also do you offer discounts for qty. of 5 and 10 packages?

The A6 folded cards are made from 65 lb cover and come to you flat, but due to the nature of this recycled  and light weight card stock, we cannot guarantee that it will not have a slight curl to it. You are welcome to order a sample before placing a larger order. Discount Quantity breaks are offered in the listing.  You should be able to choose a 250 pack from the drop down menu and this offers a discount over buying them in 25 packs.