I am using the plugin to book appointments for taxi fares. I would like to be able to add a few fields like the number of passengers and the quantity of luggage (number again). I would also like to be able to change the labels of a couple of the existing fields in the form. Ideally, if possible, it would be quite convenient to be able to have a From and a To dropdown list or text field, so that customers are able to define a meeting point and a destination for the transportation. How can I go about any or all of the above? Thank you in advance.