Norway trip this year - advice please?

[HugoHarmony]

Hello all,
We are (lastminute as ever) planning a trip to Norway in the MH (less than 3.5t) setting off 20th May. We were thinking Stena ferry Harwich to Hook of Holland then Color Line ferry Kiel to Oslo and same in reverse about 6 weeks later. All to reduce a long drive.
Have read the threads on here but still confused sorry. Can someone simplify what I need in terms of Fjellinjen, autopass, tolltags. Am I likely to get a tolltag delivered in 3 weeks. I don't have a way of paying Kroner other than by credit card online. Can I get away with none of these?
Any help much appreciated.

 

[frwjd]

You need a ferry pass and a toll account, you will pay much more without them.

 

[Riverbankannie]

You have time to get a starling or revolut account and set up a krona account to link to the ferry pass and toll accounts.