Last December I paid £239 to Travelbag for the rental of a car from Alamo in San Diego in July. On pickup, we opted for a larger car, a Jeep Commander. An extra charge of £189 was made. On our return I contacted Travelbag and have just received an e-mail, part of which reads: “Unbelievably, the car-hire outlet in San Diego charges more to upgrade from a Pontiac to a Jeep than it does to book a Jeep from scratch, therefore Alamo have closed the case.” Maggi Wood, Romsey, Hampshire

Times travel expert, Julia Brookes, responds: The extra charge does seem steep, but, unfortunately, Alamo is refusing to budge. A spokesman said: “When a customer opts to upgrade their vehicle at the rental counter, the charge to be upgraded is based on current vehicle availability and rental rates for the season. Therefore, the charge to upgrade can vary from rental to rental, and will often not match the price that can be obtained by reserving a larger vehicle.

“This is especially true for larger and more exclusive vehicles such as a Jeep, which in this case Mrs Wood upgraded to. These are highly demanded vehicles, particularly around Alamo’s peak season of July and August, which is when Mrs Wood hired the vehicle.”

Evidently, anyone who books with Alamo needs to research the type of car they need to get the best deal in advance. Alamo says that its website provides pictures of cars available in each group, showing passenger and luggage space, to help customers.

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