Pathfinder 1E Custom magical item advice needed

[abyricus]

Hello Enworld.org forum

Me and my DM had an argument in regarding to custom item creation and I was wondering what the general opinion is about custom magical items.
I am currently interested in creating an item similair to the Robe of Arcane Heritage

but instead of it targetting a sorcerer's bloodline, I would want it to target the prestige class Cerebremancer. Currently the item gives a +4 on abilities but a +6 seems even more interesting.
According to magic item creation, how much would this cost were it to be an item for the "Bracers"-slot? How would the cost be calculated?
Other than that, would this item be overpowered or would it still remain within the boundaries? It seems all magical items are capped at a +6.
Thank you for your insight.

 

[gamerprinter]

Magic items cost twice the amount of the spell powering the item. So if a spell costs 1200 gp, the magic item costs 2400 gp. While it seems like it should matter, the material of the magic item or which slot it fills adds nothing to the cost of a magic item. You don't just arbitrarily create a magic item and give some powers, rather some existing spell is what makes the item work, so any +4 or +6 abilities have to exist in the spell for the magic item to carry that capability. As a creative process, a given magic item might provide additional abilities beyond what the spell itself does, however, its power level of these additional abilities shouldn't exceed the power of the spell.

I as a GM have no problems with my players coming up with new spells and new magic items. Since I am a game designer and publisher of PF 3PP material, I think I am a good judge of custom creation and will definitely lessen anything that seems too powerful compared to the spell powering an item. Some GMs might not allow custom creation at all - I don't know your GM and his/her opinion on that. Perhaps your GM has a valid reason for not allowing your magic item.

You should itemize what you want vs. want your GM thinks is wrong and present all the information in this thread to help you come to an ideal resolution. Saying your GM doesn't like what you've created, and not presented why, nor all the specifics of your item - then asking for our thoughts, is kind of an empty discussion.

 

[Cadence]

Aren't the prices for a lot of things proportional to the +-squared. So belt's of giant strength go +2=4k, +4=16k, +6=36k. Weapon plusses similarly go +1=2k, +2=8k, +3=18k, etc...

By that, the +6 would cost at least 2.25 times what the +4 would.