Currently in the planning stages of a Thebes Tribunal saga, and while I don't expect it to come up immediately, my players are presumably going to be looking to save up their tokens for the really good Longevity Rituals from Epidauros. And so I'm going to need to figure out what sort of Lab Total they'd be paying for.
Epidauros is a bit of a special case in the Order, because on the one hand it's exactly the sort of dedicated specialist magi with a dedicated specialist lab and reliable support from the rest of the Order that usually features prominently in char-op discussions, but on the other hand their magi spend half their time in service- a season a year each of running the hospital and of crafting longevity rituals, generally. So they're probably not going to have 40 in their Arts.
Some fiddling around with Covenants ended up with a laboratory with a total bonus of +25 to Creo Corpus Longevity Rituals, plus Aura 5, +6 for sleeping in the Enkoimeteria, and +12 for use of the Blood of Medusa, so +48 before any people are involved. The lab requires a Magic Theory of 7 (it's Refinement 4), so we can assume MT 7 minimum, so that's +55 minimum.
At this point I could go build a dedicated longevity ritual specialist with functionally unlimited resources but only half her time available for study and personal projects, and see what her Lab Total is at various ages, but I think I'm gonna save myself that headache and just say "flip a coin twice; if they're both heads, you're in luck, you get Xenias the Leper; otherwise, you get one of the other magi there."
And I'm gonna pull some numbers more or less out of thin air and declare that Xenias ("has a great affinity for healing and longevity, and is probably the Tribunal’s foremost expert in such matters.") has Int +3, MT 10, Creo 25, Corpus 30, a relevant Focus, no Familiar, and no Potency or other miscellaneous bonii (Lab Total 141 + whatever the recipient's assistance is worth), and the other magi have MT 7, and relevant Int+Arts+familiar+Focus+Potency+miscellaneous bonii of about 60 (could be Cr30Co30, Cr20Co20Focus, Cr25Co15Focus+Familiar+, whatever), for Lab Total about 115+assistance.
I'm not super concerned about game balance; frankly I'm not sure the saga's going to last long enough for it to be relevant, but I would like the numbers to be...perhaps generous, but still plausible. Compared to the Lab Totals in the mid 200s I've turned up discussion of without very much googling at all, they're downright conservative, but I'm wondering how they compare to totals other people have seen in play, and particularly how other Thebes storyguides have ruled this.