I have several entities that have calculated fields on them such as TotalCost. Right now I have them all as properties but I\'m wondering if they should actually be methods. Is
Depends, if your "properties" become mammoths and require a whole slew of business logic they shouldn't be properties, there should be a method. The example you posted looks ok to be a property. No standard way of doing it, go with your gut instinct; if it looks like it needs to do a lot you probably need a method.