I recommend changing the cam belt every five years or 60,000 miles (whichever comes first).

The dealer is giving you good advice in regards to the belt replacement but I'm disappointed to read that this vital piece of work wasn't carried out before the car was sold to you.

Given that you've recently purchased the car, I'd suggest making a complaint to the service manager of the dealership and asking them to cover the costs. It's poor customer service to expect you to pay for this within weeks of buying the car.