If you are working with a travel agent, I would ask them to make all of the necessary arrangements for you now. This is part of their job, and this is what they get paid to do. If you booked your trip by yourself, I would contact the hotel where you will be staying as well as your tour guide and ask them to arrange for a power chair. There are various companies that offer trips for people with special needs, and I can give you the names of some of these companies if you are interested.
