in a lot of instances once you’re doing with surgery and hospitalization. Even elective surgery can have variability in complexity of the cost and need; there are some surgery centers that will have flat pricing...one in OK comes to mind, but they cherry pick the most run of the mill procedures in the healthiest patients to limit cost to themselves.
A workup for an diagnosis in a hospitalized patient is the one that will be the most difficult to lay a flat price on.