Update: the HTML for the calculator field is:
<input
type="text"
name="member-totals"
value="0"
class="wpcf7-form-control wpcf7-calculator wpcf7-validates-as-calculator occf7cal-total"
readonly="readonly"
prefix="$"
precision="2"
data-formulas="(is_member1 * 200) + (isnot_member1 * 275) + (is_member2 * 200) + (isnot_member2 * 275) + (is_member3 * 200) + (isnot_member3 * 275) + (is_member4 * 200) + (isnot_member4 * 275)"
>
