Build an app for me

I am looking for a basic app to help with my business needs and potentially sell this to other business. I’m not sure how it works so I’m looking to have a consult about it all before we even start. It will be a checklist style app to ensure proper QC on every job that we do. I want to be able to add pictures to the app of the work and when it’s done it can be emailed or uploaded to a cloud, or both. I would like to sell this app to others and all them to be able to edit the list to customize it to their liking as well, if possible.