Alternative Magic Item Creation Rules
1. Required Skill
Unless otherwise stated, Spellcraft is the default skill used in creating magic items. If there are multiple possible skills, the caster chooses which skill to use. The base DC to create a magic item is 5 + the caster level for the item.
2. Prerequisites
The DC to create a magic item increases by 5 for each prerequisite the caster does not meet. The item creation feat for the item is mandatory. Spell prerequisites are also mandatory, but the caster may use an item that replicates the spell or another caster that casts the spell for them. Additionally, potions, spell-trigger, and spell-completion magic items cannot have their prerequisites substituted in this way.
3. Cost
Magic supplies for items are always half of the base price in gp. For many items, the market price is equal to the base price. Armor, shields, weapons, and items with value independent of their magically enhanced properties add their item cost to the market price. The item cost does not influence the base price, but it does increase the final market price. Additionally, some items cast or replicate spells with costly material components. For these items, the market price equals the base price plus an extra price for the spell component costs. The cost to create these items is the magic supplies cost plus the costs for the components.
Example with independent value
A +1 longsword has a market value of 2,315 gp. Of this price, 315 gp is for the longsword itself (including the masterwork component) and the base price is 2,000 gp. Therefore, the cost of the magic supplies is 1,000 gp, making the total cost to create 1,000 gp.
Example with a costly material component
A scroll of raise dead created by a cleric has a market value of 6,125 gp. Of this price, 5,000 gp is for the material component and the base price is 1,125 gp. Therefore, the cost of the magic supplies is 562.5 gp and the material component is 5,000 gp, making the total cost to create 5,562.5 gp.
 4. Time
Any place suitable for preparing spells is suitable for making items. Creating a magic item requires 8 hours of work per 10,000 gp in the item’s base price, with a minimum of at least 8 hours. Potions and scrolls are an exception to this rule. Potions take 2 hours to create and scrolls take 2 hours for each spell scribed on the scroll. The character must spend the gold at the beginning of the construction process. This process can be accelerated to 4 hours of work per 10,000 gp in the item’s base price by increasing the DC to create the item by 5.
The caster can work for up to 8 hours each day. They cannot rush the process by working longer each day, but the days need not be consecutive, and the caster can use the rest of their time as they see fit. If the caster is out adventuring, they can devote 4 hours each day to item creation, although they net only 2 hours of work. This time is not spent in one continuous period, but rather during lunch, morning preparation, and during watches at night. If time is dedicated to creation, it must be spent in uninterrupted 4-hour blocks. This work is generally done in a controlled environment, where distractions are at a minimum. Work performed in a distracting or dangerous environment nets only half the amount of progress (just as with adventuring).
Adding New Abilities to Existing Items
The cost to add additional abilities to an item is the same as if the item was not magical, less the value of the original item.
Example
A +1 longsword can be made into a +1 flaming longsword, with the cost to create it being equal to that of the +1 flaming longsword (8,000 gp base) minus the cost of a +1 longsword (2,000 gp base ), which is 6,000 gp base.
If the item occupies a specific place on a character’s body, the cost of adding any additional ability to that item increases by 50%.
Example
When adding the power of a ring of invisibility to a ring of protection +1, the cost would be the price of the ring of invisibility (20,000 gp base) multiplied by 1.5, which is 30,000 gp base.
Unique properties from unique magic items and sets cannot be added to existing items, nor can they be created as an item that occupies a different item slot than the original.