How Many Times does a Client Need to Sign a Waiver?

Well... that depends on how you set up the waiver. 

Once a client signs a waiver, then that signed waiver is applicable to any and all classes or memberships associated with that waiver. The only time a client will need to sign additional waivers is if a new waiver is created for a service, or if the waiver for their current selection does not match one that they have previously signed.

The client will need to sign the waiver prior to every session, or with every associated purchase.