Yes. Thousands of businesses that don't offer a standard fixed length service use BookFresh to offer online appointments. We recommend you create a service called "Introductory consultation" and make it 30-60 minutes in length. This allows prospective customers to easily engage with your business and gives you permission to initiate a sales meeting with the client. When customers discover your website they want to take action immediately.
By offering a way for them to schedule an appointment you are providing a meaningful way for them to take the next step.