Summoning up a shopkeep, balanced for first level?

[Jack Simth]

Seconded. Compare with Rope Trick: Rope Trick is (essentially) a summon inn. Summon merchant the the same level of "handy".

Not quite. At 5th, an Extended Rope Trick is a virtual Summon Inn (so you can get 10 hours out of it, rather than 5 - you need a full night's sleep). At 10th, a regular Rope Trick is a virtual Summon Inn.

In both cases, though, you have to provide your own meals.

 

[JiffyPopTart]

I would change the casting time to 10 minutes or some other out-of-combat amount of time. It should take the merchant awhile to gather up his stuff if you call him while he is eating dinner. Although it could be interesting to start conjuring merchants into the middle of battle just to see their reactions.

As to the actual level of the spell, I would have it 1st level but scale up in availability based on Caster Level. Thus a 20th level wizard casting "Summon Shopkeep" could summon up a merchant who deals in the rarest of items, or even magical items depending on your campaign, while a first level wizard gets some street vendor who is lucky to have a greatsword.

DS