Hua Hin is a microcosm of Bangkok for shopping. There are
fake watches, beautiful silks, more handicrafts than you
know what to do with, and more tailors than can possibly make
a living.
Remember they do this every day and you MUST bargain hard - it
is easy to pay more than 10 times the fair price, but it is
also easy to get a good deal with some patience, a lot of
smiles, and some cultural savvy. If you haven't been in a
bargaining society before look and ask prices a LOT, before you
ever make an offer (once you make an offer it is expected that
you really mean it and will buy if a satisfactory price is
reached - it is really bad form to bargain, get your price and then
not buy).
If you are going to be in Bangkok - wait to make your purchases
there - you can generally beat the best price in Hua Hin by at
least 20% in Bangkok (this does not apply to fixed price items
like books).