This can vary a lot from client to client, depending on the issues that you bring. Some people like to have a long term working relationship, and they view Counselling as a regular investment in their health like you might think of a gym membership. Having a regular weekly slot can really help to build momentum and tackle issues in a timely manner as they arise.
Others come to explore a specific issue so may only require a few sessions.
I generally suggest starting with an initial 6 sessions or so. This way we can build a rapport, and then review how helpful you are finding it and how you’d like to continue.