Just a heads up. GF and I attempted to go into Hua Hin again today for a visit and get a few things and it is utterly jammed. Every place is packed and booked and my GF said on a few Thai sites that owners are gouging people on prices. We saw car loads of people with personal belongings jammed to the roof and trucks loaded with gear.
I would definitely call and confirm prior to making your way south. There are probably some places available but they are certainly off the beaten path.
Anyway just wanted to inform folks considering this option.