This should be listed in the Info section of the hotel description. Many rental agencies offer car accessories such as child seats, ski racks, tape players, etc. Yes, however, modifications may cause rate changes. Car rates can change daily, even hourly, so changes you make to your reservation after confirmation can affect the original rate. No, taxes and insurance are not included.
Many rental agencies offer shuttle service.
You will need to ask about this at the pickup desk. This depends upon availability at the time of your arrival. We cannot guarantee make or model.