Nice job! The forging process is not simple so it’s a real feat to craft a hammer like that one.
But I will reiterate the advice others have pointed out, more than 8/10 damage on a diamond hammer goes to waste for anyone with perfect skills. As for pricing, I’m a huge nerd so I wrote a program that simulates the forge process and uses prices from google sheets to determine how much it costs per craft. If you follow Vansten’s excellent strategy for an AOE hammer exactly then the raw material cost for deck ingredients for a t6 hammer (8/10 damage, 4/5 effect adjacent, 7/10 speed or durability) is about 3650 if you shop around a bit. If you include the 900-950 for a diamond hammer, the result is around 4600 in raw materials. Although I should point out you can actually reduce the number of pastes used in that method to cut down on costs if you only want to reach the 7/10 rank for speed or durability. Factoring in the legwork to buy ingredients, time to make the deck components, and effort to actually forge the hammers then 7000-8500 per hammer is a fair estimate. Personally, I have sold hundreds in bulk at 6k each, hand traded low quantities at 7k, and sell them at 7.5k on stands.