1. Pricing. Do I specify a price? Does the designer give a quote when I ask them for feedback? What's a typical price range? How are payments handled?
2. What's the turnaround time? Should I see feedback in 24 hours? 1 week?
3. What can we expect for feedback? Is there some kind of tiered system, so I'll receive X for $50 and Y for $100? If not, are there any examples of what I'll receive? I wouldn't want to pay $100 for someone to write a short paragraph of generic feedback I could expect anyone off the street to provide in 5 minutes.
2. You should agree on that with the designer when you are requesting the feedback.
3. It really depends on the designer. Some people might tweak your designs on Photoshop/Illustrator, others might send you hand drawn mockups or just notes. Our designers have been curated by the community, based on the quality of their previous work and so you should expect insightful feedback. Also if you're looking for something specific, like Photoshop edits for instance, you should mention that when requesting the feedback.