I'm considering purchasing a hip flask. My last one (a rather beautiful piece) rusted from the inside after not being used to a few years. I'd usually be carrying Whiskey or Brandy in it. eBay has several listed starting such as THIS which ships from Hong Kong for only $3.76. Granted, it's stainless steel instead of covered with leather, but I don't mind that. Now I have 2 questions: 1) Whether I should buy a cheap one like the link I posted or invest in a more expensive one. 2) How can I prevent the flask from rusting up again? Thank you for your time.