The vehicles at the JCT600 dealership in Wheatley Road, Doncaster, were damaged by a group, including five youths, aged between 14 and 17.
The crime took place at around 9pm on January 29.
South Yorkshire Police are appealing for anyone with information to contact the force.
A police spokeswoman said: "Officers in Doncaster are appealing for information following criminal damage to vehicles at a Doncaster garage.
"At 9pm on January 29, we received reports of youths causing damage to a number of vehicles on the forecourt of JCT600 dealership on Wheatley Road.
"The damage caused to the vehicles is estimated to be around £50,000. It is believed the group included around five youths, aged between 14-17 years old, wearing dark clothing.
"Since the incident officers have conducted local enquiries in the area and at other local dealerships, they are now urging anyone with information to get in touch."
Anyone with information can call police on 101, quoting crime reference number 14/22941/21.