Please open the Email Reminder > Contacts menu page and recheck field names of the imported bookings.

Probably you will see many other field names that you do not see in the Rules page, such as cost or pay_status, which will define the cost of the booking and payment status.

For ability to see these 2 fields at the Email Reminders > Rules page, please open the Email Reminders > Settings > Contact Form page
and before last

</div>

add the code like this:

    <div class="contact-form_field_group">  
        <div class="contact-form_field">  
            <label for="[cost]">Cost:</label>  
            <input type="email" class="edit_contact_text_values" name="[cost]" id="[cost]" value=""/>  
        </div>  
        <div class="contact-form_field">  
            <label for="[pay_status]">Pay status:</label>  
            <input type="text" class="edit_contact_text_values" name="[pay_status]" id="[pay_status]" value=""/>  
        </div>  
    </div>    

It will add 2 fields to this form.

Now, you can open the Email Reminders > Rules page and configure your additional conditions by using [cost] and [pay_status] parameters.