How do you price your work?
All my pricing is based on my hourly rate. Projects are priced based on the estimated amount of time they will take to complete, and retainers are priced based on the number of hours per month.
As I mostly work with startups, I have found that this way of pricing fits their needs the best. They usually go for retainers, as it's easy to see how they fit into the monthly budgets, burn rate, sprints, and so on. And since everything is based on an hourly rate, they can easily estimate how much additional work would cost them.