Enlarge Person Potion 250gp, Why?

Both the SRD and DMG have a potion of Enlarge Person at 250gp, doesn't
appear to be any errata changing this. One of my players bought some
at 50 gp during down time out of game (I allow them to buy standard
items at standard prices without consulting me).

When I saw it was listed at 250gp I made him toss down the extra cash,
but it seems odd. The scrolls are only 25gp, so it's not an extra
200gp material component they forgot to mention in the PHB. The only
thing I can think of is it's supposed to be caster level 5, but there's
no note of that in the DMG, and you normally assume potions, scrolls,
and wands are made at the lowest possible level unless otherwise noted.
There's no reall reason to make it CL 5 either as it lasts a minute
(10 rounds), maybe 2nd level for 20 rounds, but no reason to make it
5th, if a combat is going on that long...

- Justisaur

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