We had 6 weeks there earlier in the year, and wild camping trivial.
Far too many other motorhomes though.
We used motorhome parkings app (campingcar infos) on Android and it was useful to locate water/waste, and would recommend it.
As above, food & drink vvvvvvvvvvvvvvvvv pricy in Norway. Sweden better, Denmark OK
You may hear wild camping is banned by law in Denmark. It is. But overnight parking is fine. (So no bbq, chairs out etc etc)
ETA: Had around £80 of toll invoices from Norway since our return (about right) - none from Sweden