Trial of a subscription plan

I think this would be neat to implement to make the sales process even easier. For instance, being able to offer a trial of a subscription plan. Lets say you offer a 7 day trial that would be $199. A client signs up to the parent subscription plan, after the trial they wont be able to request anything else, almost like locks the taskboard.

It gives them the chance to either leave or say upgrade, they then join the full subscription plan but the first month of that plan is reduced by the trial week fee.

does that make sense? this way the client can choose to either continue with the service or leave, they can then in the future rejoin the board by upgrading.