As the rsident item crafter in my campaign, the prices I charged fellow party members wasn't really externally consistant. See, it was largely derrived off of how much my character liked the other characters.
The fighter who lent me the 300 gold so I could buy a blessed book, then told me not to worry about it because "That's what friends do." gets priority treatment and all enchantments at cost. The ranger, who I talk with often, gets a slight mark up. The cleric, who is rude, and really really likes rasing undead (something my character is uncomfortable having around) has to pay even more than the others for the same work. The new, nosy, but friendly rogue pays somewhere in the middle.
Mind you, as I handle most of the money division, I tend to take a % off the top for things like identify spells, material components and other assorted things. It's like a party fund, but just for me.
I do my best to make sure my friends are equipped, but I do more of my best for the ones I know I can count on and the ones who'd do the same for me.