What is the cost in july and what airline.... ? Recommended hotel in the 20 u.s per night range... thanks all...
Are there flights between Rach Gia and Phu Quoc? I you could only travel by boat between them.

I thought the same as #1. Flight from Saigon is around US$100. I didn't stay in Rach Gia, so I don't have a hotel recommendation there, but I stayed at a nice place on Phu Quoc called Kim Nam Phuong resort. Here is my review on Travelfish.
Have fun. Phu Quoc is beautiful.

I got a free return flight from Saigon with my Australia to Vietnam ticket. It's about $30 one way from RG I think, but is cheaper if you buy a week ahead. Only Vietnam airlines flies there at present. I stayed at Tropicana for $20 for a garden bungalow, no power most of the day though, but it was pretty good otherwise- swimming pool, good restaurant, pleasant staff. They will pick you up from the airport too.

there are DEFINITELY flights via Vietnam airlines between Rach gia and Phu Quoc. the boat is no fun at all - cramped, long, not all that safe depending on conditions and nothing to see scenery-wise - the plane is fast, simple and comfortable. the flight only costs about 20 or $30 more than the flight though can't remember exactly how much. definitely worth it.
stayed at bo resort on ong lang beach for $25 a night - quiet and very pleasant location.

Check out www.vietnamairlines.com for flight schedules and routes. Best if you can buy the tickets while in VN. The cost is 2-3 times more if you buy from outside VN. Flight options over the weekend can be limited as seats fill up fast.