I haven't seen if such a guide exists, but I write it anyway. It deals with Blacksmith of mammon price when upgrading. What I write is a theory but it worked on the cases I tried it, so I believe it is correct.
When someone wants to upgrade a weapon using blacksmith of mamon, a price in ancient adena is required. But how much? My theory to calculate this in advance is based on the fact that all things ingame have a fixed value. Of course it is not always easy to know this price. From some observations I made, I came to the following conclusion: The D-grade crystals have an ingame price of 660 adena and the C-grade ones a price of 3000 adena. When you upgrade your weapon through mammon, you pay the crystals difference but in ancient adena. Examples: Upgrade to bonebreaker (3272 D-crys.) from a tarbar (2545 D-crys). That is 3272-2545=727 D-crys. If we multiply by the ingame price (660) then we have 727X660=479,820. Rounded up is 480k ancient adena and that is what mammon asks. Another example: Upgrading to a Yaksa mace (2452 C-crys.) from a war axe (1720 C-crys.). Again 2452-1720=732 C-crys. Using ingame price 732X3000=2,196,000 ancient adena. If we round it up it is 2,200,000 ancient adena which is the price the mammon asks. Having these in mind, you can calculate the ancient adena you need for any upgrade. I haven't checked yet what happens when it comes to upgrade from top D to low C. I'll try to find out
PS. If someone finds a case that the above doesn't apply to, please post.