“At the (rental car) window it turns out they can ask you whatever they want.”
The employee said the minimum price to rent the car might be 20 euros (£16.65) and they could ask for 3,000 (£2,496).
They added that the rental company forced them to try to “swindle the client” for extra money.
The former worker said: “People earned below the minimum wage and a two percent commission on the extras such as insurance or an upgrade to a better car.”
They claimed the boss regularly made threats to employees who had sold the least that week.