that high end
No, you can do with a lot less. For example, I have "only" a 120 Ah AGM battery (no lithium) B2B charged by the van (60 Ah effectively useable) which gives me all the power I ever need - for refrigerator, light, fans, drone and camera charging, etc.. A few hundred Euros. No solar.
If I find myself in need of stationary charge down the line I'll buy a foldable solar panel for another 150 EUR or so, that can be turned towards the sun while the vehicle is in the shade, or it's used as a window shade. I also have a standard mains charger on board to hook up the battery in a campground. Cost 50 EUR.
Much of the stuff "everybody" is doing is cool but idiotic. 500 W of solar on the roof at the worst possible angle (especially in winter) so you only get a 20% yield. Waste of money.
You just have to think hard what you really need.
That all makes sense. Have you considered doing a post on your van conversion? That would be cool and I'm sure people would find it interesting. I would anyway.
I thought about it, but I was in a rush to get it done A.S.A.P. and took no photos or video. That will make it hard to explain stuff.
BTW, the van is not finished yet. There is insulation on the doors and a lot of trim still missing, but it's fully usable. It was too cold to work and I couldn't go to the home center for the longest due to COVID. (Refuse to get tested or vaxxed.)
I will make a post about my layout. It's different from anything I've seen and gives much more room. Most notably a huge 200x160cm bed for two.
My kitchen is in the back (as opposed to the side). I can cook inside or outside, it houses a 40 l fridge, 45 l of fresh water, 22 l of grey water, and a full complement of kitchen utensils.
That layout sounds awesome.