When we booked our trip from Bangkok to Siem Reap in Cambodia we took a package that included one night at Sawadee hotel in Siem Reap. While this is a nice hotel to stay at with a good restaurant attached and nice staff here is a word of warning.
There is a guy working at that hotel as a travelers guide that will try everything and anything to sell travel packages to you directly when you arrive. We ended up with a 9 day packade including 3 days at the tempels around Ankor Wat, bus to Shianoukville, 3 nights in a hotel in Shianoukville, bus to Phnom Penh, 3 nights in Phnom Penh and transport to Saigon in Vietnam. All for 590 dollars.
It sounded like a good deal in the beginning but what you need to know is that this is at least double the price from what you can get on your own. On top of that you will need to confirm everything as you go along and you will realise that nothing is really booked which means that we paid only for the names of the different hotels and companies for transport. It was really a nightmare to get everything sorted at the different locations.
Tip: Just do it yourself.
Note that a trip to the tempels around Ankor Wat is about 2 times the price that you can get in town, with that said the guides employed by Sawadee is really terrific. You will need to pay an extra 40 dollars entrance fee for 3 days at the temples.