Camper van values have traditionally been very robust against depreciation, However, since the pandemic, values have gone into overdrive. And all generations of the California are currently commanding strong money: vans.honestjohn.co.uk/vans-for-sale/campervans-mot.../

I don't think this will change in the foreseeable future, as the T3, T4 and T5 all have huge followings in the UK and Europe. If anything, the 2030 ban and the switch to electric could make the T6 a collector's item due to it being the last of its kind.