I find after getting in and out with wet feet the condensation is worse in the morning
I bought a bag of crystals from the range. That draws moisture out of the van it hangs on the little hook on the side of the pillar in the front footwell. Once the orange crystals go white you microwave it to recharge. Works a treat. £4.99 I think
Get an external windscreen cover. Taylormade or silverscreen both are thermal & stop screen getting so cold so no condensation when sleeping in Cali. Both do the job & are priced about the same.