Corrupt officials at the Cambodian side of the border wants more money than what a visa actually costs. Be prepared to pay more...
Unique Suggestions: Here's our story: The officials at the visa section first suggested 1200 BATH for one visa, then saying we couldn't pay in USD.
Before my trip I had read on the official Cambodian webpages that a visa cost $20. I asked the two officials to see a written confirmation of the price, which they denied to show me. I didn't want to pay 1200 BATH. Then they asked me to go outside waiting for the boss. When the boss came the two officials could no longer speak English. I explained the situation to the boss and he said I could pay in USD and that it probably was a mistake. He asked me to suggest how much I would pay for a visa. I said $40 for two as that is the price. He said then he couldn't give me a visa as the office needed what he called a "donation". He explained the government didn't pay for the air condition or enough salary for his staff. He wanted more money.
I spent about one hour at this border post. A very bad start for my Cambodia trip. I ended up paying $50 for two visas and then the boss acknowledge that it should have been $40 but that he didn't have change. He also said we now had agreed upon this small donation. I said I would report this to the authorities. Then the two other officials suddenly knew English again. They said then I would not get a visa.
Anyway, I think this is a bad way of treating tourists. The border posts and visa offices should have written statements from the government what the price for a visa is, so that no one get cheated.
We were the only two at the border between 4pm and 5pm that evening. Later in the day some friends of ours experienced the same. They had to pay 2500 BATH for two visas. They also had to pay $1 for electronic photo with the police. This we didn't have to.
Fun Alternatives: I encourage you to report this to the ministry of interior and ministry of tourism when you get back. Email: email@example.com, firstname.lastname@example.org, email@example.com