Template.wizardReview.onCreated(function () {
  // Get reference to template instance
  const instance = this;

  // Get form data as instance variable
  instance.registration = instance.data.wizard.mergedData();
});

Template.wizardReview.helpers({
  'registration': function () {
    // Get reference to template instance
    const instance = Template.instance();

    // Get registration from template instance
    return instance.registration;
  }
});

@@ -441,16 +441,564 @@
 ration;%0A
+  %7D,%0A  'accommodationsFee': function () %7B%0A    // Get reference to template instance%0A    const instance = Template.instance();%0A%0A    // Get registration data%0A    const registration = instance.registration;%0A%0A    // Adjust attributes of registration data to match accommodations fee function%0A    registration.type = registration.registrationType;%0A    registration.ageGroup = calculateAgeGroup(registration.age);%0A%0A    // Calculate accommodations fee%0A    const accommodationsFee = calculateAccommodationsFee(registration);%0A%0A    return accommodationsFee;%0A
   %7D%0A%7D);%0A

Add accommodationsFee helper