Wizards can create items more cheaply than sorcerers.

The pertinent rules here are in the general magic item creation section and magic item gold piece values sections rather than in the individual items, respectively:

While item creation costs are handled in detail below, note that normally the two primary factors are the caster level of the creator and the level of the spell or spells put into the item. A creator can create an item at a lower caster level than her own, but never lower than the minimum level needed to cast the needed spell. Using metamagic feats, a caster can place spells in items at a higher level than normal.

Prices presented in the magic item descriptions (the gold piece value following the item’s slot) are the market value, which is generally twice what it costs the creator to make the item. Since different classes get access to certain spells at different levels, the prices for two characters to make the same item might actually be different. An item is only worth two times what the caster of the lowest possible level can make it for. Calculate the market price based on the lowest possible level caster, no matter who makes the item.

Not all items adhere to these formulas. First and foremost, these few formulas aren’t enough to truly gauge the exact differences between items. The price of a magic item may be modified based on its actual worth. The formulas only provide a starting point. The pricing of scrolls assumes that, whenever possible, a wizard or cleric created it. Potions and wands follow the formulas exactly. Staves follow the formulas closely, and other items require at least some judgment calls.

As the sorcerer gets access to the spell later, it would cost them more to create the item. Staves specifically are called out as following the formulas closely and don't mentioned anything specific to override the baseline rules around spell/caster levels (although as noted by Hey I Can Chan, this would be a custom staff).