Could you add a category for pricing that is called either Variable or Tier pricing? When I photograph products on white there is typically a tier pricing schedule. Using N/A sounds negative and it really not related anyway. Also, when I do a contract for product photography, there is a lot more that goes into it, and not just a price. When I don't use Thumbtack, there is a whole contract worth of information that takes time to write; its all custom work. I'm not sure if there is a way you can indicate that the vendor will have additional info to provide.