Crafting wondrous items

[rhammer2]

There is a maximum plus a caster can bestow on an item, it is +1 per 3 caster levels.

See DMG p217 for Caster level for Armor and Shields, p221 for weapons, p232 Ring of Protection. In 3.0 there was the same restriction to stat enhancers, but I don't see it in the 3.5 descriptions.

Followup question: is there a caster level prereq for creating items? For instance, what's to stop a 3rd level caster from crafting a +6 stat item? I suppose the GP cost, because XPwise, it's a big chunk, but doable.

In item descriptions, there's a caster level listed, but that's the effective caster level for bought or found items, I believe; I'm fairly certain it's not a prereq.