Stored Procedure examples for Public Events

I am trying to determine where in iMIS15 an organization might use the Stored Procedure in Registrant Class of Public View.

I wonder if anyone has any ideas on how I might do the following in Public Events:

 

1 -- Give a discount for Events pricing when more the 3 people register

2 -- The pricing is determined on whether or not the customers have purchased insurance.  We have setup INSURED & NONINSURED registrant classes which works when the registgration is processed in-house.  How would this get selected when a member registers in Public Events?

 

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