I buy my styrene in 4 x 8 foot sheets from a plastics dealer, and cut off what I need. A sheet costs me about $16. In Albuquerque it was available in .010, .020, .040 and .060 thicknesses. It's a lot cheaper than buying from a hobby store. I can order it here in Oxford, Ohio from a local sign painter, or drive about 20 miles and get it myself from the source. It rolls up into a tight cylinder, so it's easy to transport. I brought two sheets with me on the last ABQ-Oxford run.