Service with variable pricing: If you'd like to set variable pricing for a specific service, set the service price as Varies. If you would like to offer different versions of the same service, each with a different price point, you can do that under Duration / Pricing. 

Service with variable duration: If you'd like to set multiple durations for one service type, you can do so under Duration / Pricing. For example, you can offer a Haircut service for long hair (1 hour) and short hair (30 mins).