How to avoid fines for the unlawful use of Hungarian roads?

Although the HU-GO distance-based toll system has been in operation since 2013, many transport companies still pay high fines for the unlawful use of Hungarian roads.
Since November 2017, after a revision of the penalty rules, the amount of administrative fine depends on the duration of unauthorised use and can range from moderate, through normal to high.
The toll is obligatory for all vehicles with a maximum total permissible weight over 3.5 tons and its rate is determined depending on the type of road (motorway, expressway or main road), vehicle category and its ecological classification. The toll is collected on a total of 6,500 km of roads, which cover nearly all major routes used for road haulage.