The rule for determining sale value of a spellbook is:
Captured spellbooks can be sold for an amount equal to half the cost of purchasing and inscribing the spells within.
Yet when I look at the listed values of the prebuilt spellbooks (here: https://www.aonprd.com/Spellbooks.aspx), it seems they only factor in the inscribing cost for the spells and not the purchasing cost for the spells as mandated by the rule I listed above.
What is the correct way to value a spellbook?
I don't believe there is a specific rule for spellbook values. I've never been able to find it.
For my campaigns I use the following...
If there is a spellcaster in the group that can use the spellbook, then I generally don't allow them to sell it. The value becomes the availability of the new spells the have immediate access to. I consider it "double-dipping" by copying the spellbook into their own, and then selling it.
If there isn't a PC that can use it, or it has spells the PC already has in their spellbook, then it will sell for half the scribing costs of all the spells within it, minus the 0-level spells. 0-level spells are so common that they are mostly worthless to anyone who would want to purchase it.
As a GM as part of my prep, I will usually add the number of pages used and the gp value so to save time during the game. I feel the number of pages are good because I've had some PCs start using the empty pages of the new spellbook for their own scribing.
Thanks for your response, but it doesn't quite address my question.
The magic section that I quoted and linked in my first post has the official rule from the CRB about spellbook valuation, yet the prebuilt spellbooks do not seem to follow those rules.
Many of them contain little rituals, which would obviously increase their value (since they have an effect).That aside, you are correct.
Maybe the devs changed their minds, so maybe spellbooks are now worth only the cost to inscribe the spells into the a spellbook.
Regardless, the cost of buying spells is not set in stone. The caster could charge anything they want. Half price is the normal rate, but a caster with rare spells might charge more. This can make judging the cost of spellbooks difficult.
Trying to look at the fine details, copying an existing spellbook costs you half the time and money than normal. The price you could sell a spellbook for is also half the normal price. If you tried to add in the price of the privilege to copy spells, you would then get a profit. So I think the rules were changed so it would be more difficult to game the market.
Trying to look at the fine details, copying an existing spellbook costs you half the time and money than normal.
Only when replacing a lost spellbook or copying your spellbook to make a reserve copy (always a good idea).