Members and their prices
Members have their own prices, even when you have agreed something different with one person than with the rest. A member sees their price right at booking time, so nobody at reception is arguing over whether the discount applies.
Coaches and training sessions
Coaching hours, one-off or recurring, hold their place in the schedule and nobody books over them. A coach manages their own schedule and does not have to come to you for every change.
Who may do what
Everyone at your club sees what they need for their job, and nothing more. You invite new people by e-mail, so nobody shares one login and nobody has to remember passwords.