I wouldn't use a buffered reader for keyboard input, since Scanner was introduced 11 years ago. You can print a request and get the data from the keyboard in the appropriate format. Get that working and get the data into a Car class. Then consider writing the XML later.
I would have a Car class that has a String toXML() method. And perhaps a Cars class that manages a list of Cars; also with a String toXML() method. Cars.toXML() will be responsible for iterating through the list and calling the Car.toXML() method on each one.
The most difficult part of wild life photography is getting them to sign the model release.
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