Don't forget motels (self contained accomodation) as an alternative. Yes Jan is school holidays and camping has become very popular again because of the recession. I would try and book as much as possible.

And also remember that we don't have much of an ozone layer anymore so sunscreen and long sleeved shirts/arm coolers are a must. 10 minutes and you can be badly burned. Reapply frequently as well.

Have fun!