We booked spontaneously a day before but I recommend booking earlier depending on the season. In any case, we were informed about expiration and so on in time. The two tour guides we got were super nice and accommodating. They gave us many helpful tips and always sought the conversation so that it never got boring. Initially I had my concerns about riding the scooter in Vietnam but after 2 minutes with my guide the fear was gone because it rode great.It was super fun. Thank you!