These days the difference is minimal. With customers being pretty much able to anything they want to online then the only reason they would use a travel agent would be for the level of support and service that they can give them.
For that reason, the price through a travel agent provinding a decent level of service on a flight only booking is more than direct as the customer is prepared to pay for personal service. The net fares around now are measured in pounds rather than huge discounts. You also lose a lot of flexibilty when going through an agent as it is harder for VS to play around with the ticket before travel.
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