You can check whether a car has a valid Digital Vignette in a public register. This will reliably tell you whether you can drive this vehicle on motorways and expressways. While this used to be obvious just from looking at the windscreen, now you have to enter the registration number online. The register does not include any other information, such as about the vehicle owner.
Per day, the register can only be accessed three times from the same device (desktop, laptop, tablet or smartphone). This means that it is not possible to carry our comprehensive checks.