So, I guess what we're looking at is:
-sell the warhammer
-sell the potion of resist energy (fire)
-sell the potion of bull's strength
Everyone gets 1543gp, except Zoe, who gets 1193gp and the potion of cure moderate wounds.
Basically, she gets 300 less for the potion, and everyone else gets 50 (300/6) more from Zoe's share, to represent her 'paying' for the potion.
If Zoe also wants the potion of bull's strength, then everyone gets 1543gp and Zoe gets the two potions and 843gp.
She gets 600 less for the potion, and everyone else gets 100 (600/6) more from Zoe's share, but 50 (300/6) less, since there's one less potion to sell that goes into the group fund.
I think I did that correctly. I'm going to assume the first scenario (since I'm about to start fiddling with my character sheet), but let us know. Also, if anyone wants one of the other potions or changes their mind and wants the warhammer, let me know and I'll refigure the numbers.