Vimeo has an in-house Apple instructional video showing how to prepare for data collection and how it is collected by the team of Apple engineers dealing with maps using a special car equipped with a team of LiDAR cameras and scanners.
The company uses Subaru Impreza cars to collect data for Apple Maps. The video below shows, among others, the 2013 Mac Pro and NAS with SSDs, on which data backups are saved. They take about a week to fill. The whole system is controlled by means of EyeDrive application installed on a specially modified iPad.
Interestingly, the team works when the angle of sunlight is higher than 30°. This is to prevent disturbance of data collected by LiDAR.
It is worth to watch the entire video below before it is deleted on Apple's request.