Work out what a custom Spheres of Power magic item costs to buy and to make, using the talent-based item creation rules on Magical Items. Pick a base sphere and base power, then add the talents, feats and other changes your item uses; the crafter tracks complexity, price, materials, crafting time, the item creation check and what the crafter needs. Spell engines, implements, charms and magical weapons and armor are priced from their own tables. Your items are saved in this browser as you go. Open the crafter in its own tab if you want more room.