The government did a u-turn on including motor caravans in the passenger vehicle tax bracket in 2020. From April 2017 until then, they were taxed the same as cars and so attracted the higher first year road fund charge based on emissions, and the additional £355 per year road fund licence for vehicles over £40k, for the next 5 years. After lobbying from the industry they accepted it was unfair as you couldn’t purchase a motor caravan for less than £40k. So from April 2020 they allowed motor caravans to be taxed as light goods vehicles.