I am passing through Hua Hin for a cuple of nights at the end of November, and haven't chosen a place to stay yet. My questions are, should I book a hotel in advance or will I be OK just turning up and finding something? Also, are all places Guest Friendly or do I need to check that first?
You should be fine without booking as long as your stay doesnt coincide with a Thai holiday (Loy Grathong is this month). At these times the town gets swarmed by Benz driving Bangkokians.
Most places are guest friendly although some may ask for an ID card for security purposes.