The rental option

Hmm well there are vans for sale but as you say they don't fit your criteria, and that is important. You don't want to spend loadsa drinking vouchers only to find you don't like it. And you do have a big advantage of experience and knowing what you want.
Just wait - a month after we are allowed out, you might find that someone bought one and doesn't like it so are selling. I think there will be a lot for sale in the months after freedom.
If you have the dosh and find one you like, just remember that one day you will find you can no longer drive. Then the day will come, as my dad surprised me one day by saying "You have the money, I can't spend it". Thanks, dad - but he was right . He was living with us / we were caring for him and he couldn't spend any money. Then the day will come when you can't take it with you. To me, that legitimises just having a piece of machinery on the drive that was superbly well made (in 2008) that I can enjoy just sitting in it and modifying bits of trivia.