First of all, this post is written by a player, but my DM will be looking in for advice as well as this is a problem we're trying to solve together, not something where we're 'against' each other.
Next, it has several interlocking parts, including pricing of a custom magic item, which could be in the rules section, but advice on any of it would be appreciated.
Story as follows:
We're coming up to finishing the first book of the carrion crown AP and we're going to come into some money. My character is an illusionist wizard. not the most useful in book one, but thats not a big deal. The problem came to light when I wanted to approach my damn about making a custom magic item. Spoilers here: There are a few points in the first book where you can research stuff, with a bonus for various libraries. my characters idea was a magic item, that by copying and storing key texts, could 'keep' up to 3 of said bonuses at a time to be able to research in other places, like in book 2, if something was somehow relevant.
My DM was concerned, mostly because (as she shared) the highest DC in book 2 is something that, should these bonuses apply, my character could hit fairly easily, and she's worried about the consequences of us having ALL the knowledge immediately rather than working for it, doing favours, etc.
It doesn't help that I planned to take bestow insight as a second level spell to boost my skill check even further.
So I guess our problem is this: What are ways to still make my character feel like an investment in skills is worthwhile, without potentially giving us all the info that will change the course of the book dramatically. She doesnt want to punish me for having a high score, because I've sunk resources into it, and now wanting to spend cash on a magic item, but at the same time, doesn't want it to feel underwhelming and too easy, or impact the book in unintended ways.
So, thats the BIG problem. thoughts, advice, etc, appreciated.
The other smaller one, which maybe i'll make a separate thread for, is how to price the magic item i want. its not similar to anything I can find, and as the groups rules lawyer, I have no idea to how price such a niche sort of thing.
What i want is two-fold. The aforementioned way to keep essential research bonuses by storing key texts in a datacube/magical tomb, etc, and a way to recall small bits of data perfectly, important stuff my character doesn't want to forget.
Thank you all for reading my wall of text, and any help you can provide would be awesome. To my DM: you are also awesome
Lots of things here, easiest first:
The price of a slotted magic item that gives bonuses to multiple skills in one slot is (bonus squared) x 100 for the first skill and (bonus squared x 1.5) x 100 for each addition skill added together.
"For items that take up a space on a character's body, each additional power not only has no discount but instead has a 50% increase in price."
I'd consider adding on a handy haversack-esque feature at 1.5 times the cost to actually capture the physical texts.
The price goes up if you're using a slot that doesn't typically work for that skill, so headband would be good here.
The price goes up if it's a wondrous item that doesn't need a slot.
There aren't rules i know of for swapping skill abilities out, as items cannot be retrained. I'd recommend simply adding more knowledge onto the item at cost.
Now as to the DM situation:
As a DM, personally I would not care if my players had a knowledge monkey who was spanking my standard knowledge checks. I would let them succeed and then add new EXTRA hard knowledge checks that led to little extra adventures, secret rooms and additionally added monsters, even in an AP. This way, the player gets to feel cool about what they're good at, but also there still is mysterious knowledge that motivates the party.
Part of what makes adventurers adventurers, and why they are both loved and hated, is that they are exceptional and disturb the equilibrium wherever they go. Maybe the smartypants adventurer embarrasses some town sages when the adventurer pulls out their datacube and the sages send thugs to get the cube. Party retribution leads to discovering a small hidden evil temple in the sages tower. The temple contains hints at additional power sources for the data cube, which it turns out resembles a set of cubes the evil god once made.