So, I have a custom item that one of my players founds after a particularly nasty boss fight, and he wants to upgrade it. I did not use the PF guidelines for creation, and thus, have no real idea of what the price (and thus the cost to upgrade it) is. I figured you folks might be able to help me.
Ring of Warping
Five times per day, you may activate this ring use Dimension Door. Once per day, as a Swift Action, you may Dimension Door to five different squares. Until the end of your turn, you are treated as though you were in all five squares and may make any part (or all of) a full attack action from those squares.
Thanks in advance lovelies!
For the basic effect it's a command word item with CL 10, a 4th level spell and 5 charges a day so 1800 * 10 * 4 * (5/5) = 72 000 gp
The 1/day effect is harder. It's something like the dimensional dervish effect which is 3 feats down a specialised feat tree, using a 6th charge per day of dimension door. As a rough rule of thumb I call a feat worth 5K, a second feat 10K, a third 15K but that's not in the rules. Another charge is 14 400 gp, the feats add 5 000 + 10 000 + 15 000 = 30 000. It's not really a separate effect so I wouldn't multiply by 1.5. Total of 116 400 gp which I might round up to 120K. This doesn't seem way out of line to me - it's an item which a 20th level character would still prize.