Those 360-degree "bird view" cam systems that fuse together four wide-angle cams to form a view do a fairly good job for both purposes. Not ideal for either, but a pretty good compromise. The are cheap and if you put a big SD card in them, the will record for a LONG time. They do not record inside the van, though. If you power it from your house battery, it should be practical to have them record all the time, although they also have motion sensing, usually. They are cute.
Another option would be the little Wyze cube cams. The current version is weather proof. You can put SD cards in them and they detect motion very well. Resolution is excellent. They are amazing for the price.
Formerly: 2005 Airstream Interstate (Sprinter 2500 T1N)
Now!: 2014 Great West Vans Legend SE (Sprinter 3500 NCV3 I4)