See this Expatify index.

Annual inflation rate of Cambodia seems to be around 6.5 per cent or so.

Here is my plan for the start of the Indochina Adventure!

PHNOM PENH
Taxi to city from aiport: Should cost US$9, according to Travelfish (2011). Buy yellow taxi tickets from the officials outside the terminal.

Entrance to the Royal Palace/Silver Pagoda complex should cost $6.50 (as of 2012).

Angkor Wat: A one-day entrance ticket costs US$20, but better value would be a 7-day non-consecutive pass (US$60), which lasts for a full month.

From Marijuana Travels: "Note that when you are in Cambodia, you can always bargain. Here, you can get about ¼ once of good cannabis for just about $2 - 5 given that you are good at haggling. However, if you choose to get your fix at a pizza parlor then it’ll cost you a little bit more. ?"