Yes, although uber/lyft is slowly making it's way out here, it's not quick or reliable. There are local taxis too, although it will be much easier to have a car or connect with someone with a car to get around.
The closer the better! There are lots of wonderful airbnbs and hotels within walking distance. We definitely suggest staying nearby, so it is easy to walk or just a quick drive to the celebration. For those who are from out of town and staying further away, note that the roads are dark and curvy as you leave Monte Rio.
Cell coverage is spotty, verizon works ok. Make sure to note your directions once you get off the 101, most of the drive off the highway is without cell coverage. Note most hotels and airbnbs do have wifi