Farecrawler is a fraud. They quote you a really good price -- much better than you have seen on other sites. You "purchase" your ticket by transmitting your credit card number. Then you get an email saying that they need to do quality checks which will take some time. So the transaction is not completed. The next day you get an email that the Airline has increased its base price but that they can offer you another deal (which is still much more expensive than the price they quoted you).

This is a copy of the email that I received from Farecrawler

Subject line: Notification of Change in Fare, Taxes and Fees

This email is to inform you that the airline has increased the associated fare, taxes and fees on the flight you booked through Farecrawler.com before we were able to complete our standard quality process checks as outlined in your confirmation email. Before we can issue a ticket we process a couple of check including a matching of the credit card details that you provided to the data on record of the credit card issuer.

Although this happens rarely, airlines do sometimes change prices and taxes overnight and we are required to collect the additional taxes and fees from the traveler. The fare, taxes and fees for the flight(s) you reserved have increased to $ xxxx.

In order to continue with the issuance of your ticket(s), we need your written or verbal acceptance of the new amount within 24 hours. If we do not hear back from you in this timeframe, we assume that you don’t want the ticket at the higher rate and will therefore cancel your reservation. Your credit card will not be charged.

However we are able to offer you the following options please see the below itineraries and if you wish to continue please reply back to this email by selecting one of the options.