I don't know about the other Nordic countries, but in Denmark we have a lot of shelters around the country, typically in forests, which anyone can book and use for a night or two. A typical price for booking a shelter is 25-30 dkk/night/person, which amounts to 4-5 usd.
Wilderness cabins are common, but I was referring to privately owned cabins since in Sweden and Finland spending time at your cabin is common.
If your aim is to have shelter and a place to get food then public/trekking association cabins are quite a good choice. The vacationing at your cabin is separate.
