A possible idea: one price with a fixed number of revisions. For additional revisions, you offer an add-on option i.e. the client can purchase additional revisions for a fee you set.
As other posters have said, offering unlimited designs might give some customers unreasonable or demanding expectations. Will an 'unlimited' option swamp you with revision requests?
Another suggestion: make your work a more prominent showcase on your website. Potential customers what to see examples of your app designs and user stories. Your current designs don't have any context - they are simply mockups (good-looking mockups) with no description. Do they need more detail and context? A case study for example. Make it clear to customers what they can get from your service - show off you work in the best possible light to catch their interest. Good luck :-)
There are good suggestions from others. I just want to say sorry if I came across quite harsh. I respect that you’re doing this at all and wish you the best of luck.
As other posters have said, offering unlimited designs might give some customers unreasonable or demanding expectations. Will an 'unlimited' option swamp you with revision requests?
Another suggestion: make your work a more prominent showcase on your website. Potential customers what to see examples of your app designs and user stories. Your current designs don't have any context - they are simply mockups (good-looking mockups) with no description. Do they need more detail and context? A case study for example. Make it clear to customers what they can get from your service - show off you work in the best possible light to catch their interest. Good luck :-)