L6 isn't something I'm familiar with, but I'll look into it and see how much it runs.
Typically Damascus costs the most, as it costs the most for me to purchase. If you're happy with a 'normal' blade though, 1095 is the cheapest and can be under $100. After that comes 154 CM, D2, S30V, and similar materials. Those are stainless and offer exceptional strength while keeping a good edge. Typically they range from $100-200. Damascus gets into the $200+ range.
The price really comes down to the cost of materials, I try to keep prices as low as I can. I'll work with you on design and materials and give you price quotes, and of course everything is negotiable.
Also, typically I do everything but make the metal itself. I even heat treat it when I can (they're are some of he stainless metals I can't do though, so I have them sent to bigger shops). All the knives are one of a kind. I do not use any templates or 'pre-made' blades. I do not have anything cnc'ed, or machine sharpened. I hand-make everything 'freestyle'.