The single session is for you if you want complete flexibility and wish to decide week by week if you want to continue counseling. This is great for people who want to test out counseling first and do not want to make a committed decision yet.
If you already know you want to receive long-term counseling, I recommend booking a counseling package. This way you get your sessions either 10% (4 session package) or 20% (10 session package) cheaper.