Hi,my wife and I are travelling to the US in January but will be organising flights separately online.I thought it might be easy but most sites seem to do return flights and one site gave a huge price.My cities are

Washington DC - Miami - Las Vegas - Los Angeles - San Francisco - Vancouver - New York

Can you advise the best way I can do these one way flights starting in Washington and finishing in New York

Thanks

By planning a string of one-way flights, you are catching the higher prices that airlines usually charge for one way tickets. Here are 2 ideas that might bring the price down for you.
First, mattering on if you want to spend only a day or two in a couple of cities, you can try to get extened layovers in a city that you are connecting through. Example: When you are flying from Miami to Los Angeles, you might be able to find an airline that connects in Las Vegas. Then you can request at the time of your purchase of that ticket that you would like an extended layover in Las Vegas, usually up to 48 hours. The cost for this usually runs from $50 to $100 but that would be less than adding on another ticket. Another possible connection would be from Los Angeles to Vancouver with a 48 hour layover in San Francisco.
A second way to save some cash would be to look for a multi-city itinerary. Our consolidator booking engine allows you to build a multi city ticket, which is usually much cheaper that the equivalent group of one way tickets. You can also find companies that specialize in multi city tickets by typing in "multi city tickets usa" in Google.
Hope this helps!