How the Backpacker Index works. Prices for most things are fixed and certain, but prices for a “budget lunch” or a bottle of beer can vary depending on whom you ask. Backpacking Cambodia – you can find gorgeous beaches, 25 cent beers, mythical mountains and steamy jungle. How to travel from Bangkok to Siem Reap (Angkor Wat) & Phnom Penh by train & bus, and by bus from Phnom Penh…