well, aside from a +5 intel book and a +6 headband of intellect, i kinda don't need anything else on my high level wizard, seriously, starting from level 13, i became the party bank, loaning money to the beatsticks, cause i couldN't find anything to do with it, my spells provided everything i needed.
and then again, those 2 are just for fuck's sake.
Dragonskin + greater mage armor= +11 to AC, just there, and that's without all other things like polymorph, alter self, mirror image, displacement, protection from evil, shield, that can all be very easily cast to send your Ac into the stratosphere, without a single GP of investment. Also, if you wanna fork over 8k gold, +1 defending spiked gauntlets can net you another +5 to AC.
Rope Trick: Suddenly, you don't sleep out in the open, and that's just before you can eventually get mordenkainen's magnificient mansion, or magnificient brothel for the kinky minded ones
And let's not even talk about genesis please... having your own plane can have it's perks.
Superior resistance: +6 resistance to all saves 1 hour/level, did i make a cloak of res useless? Yep, i sure did!
Elemental body (air): anything not flying, amongs them a VoP monk, is made useless. Anything relying on stun or death saves or ability drains or crits... heck, pretty much anything that's nasty, is made useless. ZING!!
the point sunic is trying to make in his own arrogant, pompous, demeaning way is that wizard spells replace the need for most items, most of the time, the monk cannot do that, he has to sink his money in trying, and failing, to be effective.
My lips are not glued to sunic's ass, but when he's right I'd be a fool not to admit it.
A monk has to waste way more money than a wizard to have a chance at doing something, and even then....
A wizard has to be very creative to find a use for his money.