i'm designing some adventure where a top3 specialist creator of Longevity Rituals (bonus +26 to the aging rolls) is an important NPC.
I need to know how much you would pay for this kind of potion.
He's well known in the Order (reputation 3 < Hermetic prestige) for being in the top3 best specialists of LR and is a bonisagus living in Durenmar.
Obviously, he sells his LR no less than 26 pawns of vis (that is the investment of vis used ^^).
So, how much would you pay for this kind of ritual? Of course, more you pay, sooner you get your LR... his list is going for at least the next 30 years, with 2 seasons of working by year...
(All that for him to pay 3 Verditius to do so big enchanted item that you will never see it again in History. For the BG2 likers, he's buying a planar sphere with an inside laboratory, with 10 complete rooms for guests, able to transport in any arcane connection point, repelling demons or bringing the apocalypse (like would say my aSG ) [final cost in vis for the bonisagus: 500 pawns. Yeah, it's not cheap] )
Interesting question. I don't have a good answer on a price point except that the Bonisagus might treble the cost expended on the project.
But the important factor is how badly the character needs the potion. An ancient magus trying everything to stave off the innevitable might move heaven and earth to jump the queue.
So if the NPC is simply a resource that can make a powerful potion, then set the price at what he'd charge (double or treble the vis cost).But if he's the incitement to story, then I think the actual cost is secondary; it's more about what you'll do for the potion. Would you steal for it? Kill for it? Right a wrong the Bonisagus is too proud to fix himself?
Okay.
About your advice, one of the verditius is in fact a maga 187 years old, with a LR which is really "old" (only -13) and she's taking a.p. Not enough for crisis, but time is close.
Fact is that this maga is [unprononcable name of the former primus of Verditius house] and i think has the means.
But before the adventure start, where the PC will have a role of course in all that, i need to have a price she would have give to be on the first place in the list, perhaps even in the "free seasons" of the bonisagus.
Because, i don't want to start on a "strange" base which would look unrealistic
Sounds unrealistic to keep such a weak LR while she is able to make a better one which gives +26. I can imagine she had a LR +20-22 or such earlier. She is a woman and her appearance does matter a lot.
Maybe she had an even better version, even +30 or such having good assistants, a longevity specialist patron or a magus lover before. But the lab text to that ritual is missing for a particular reason.
IOS the magi are not so cooperative.
For the maga, she has not been rich since her gauntlet. But this adventure is postponed and in conception pause. So i'll work it again when will come the time to play it
with an inside laboratory, with 10 complete rooms for guests, able to transport in any arcane connection point, repelling demons or bringing the apocalypse (like would say my aSG 
) [final cost in vis for the bonisagus: 500 pawns. Yeah, it's not cheap] )
