Let me see if I can help.
Let me start out saying that you should DEFINITELY visit Scandinavia. Scandinavia is the best place in the world in the summer.... just to bad our winters are 8-9 months:-)
It can be expensive if you are not aware of how we survive here :-)
Eating out is pretty expensive. Scandinavians love our kitchens and cook at home for the most part. Therefor its fairly cheap to shop groceries, but not to dine out.
Everybody here speak great english so just ask people if you can set up your tent. In Denmark you need approval from the ground owners before you make camp, but i believe you can do it anywhere in sweden ( obviously not on private property unless you ask.) But just ask and i can image anyone who woun't let you camp in their yard.
Here are some current prices from Denmark.
1 L of Octan 95 is EUR 1,48
A cheeseburger at McDonalds 1,34 EUR
Cheapest hotel from 67 EUR and up... you might find bed and breakfast which is 40-50 EUR... but it's not cheap at all.
Eating a Kebab is 3-5 EUR
Eating a burger + a 0.5L
in a cafe is 20 EUR
Beer in a supermarket is 0.4 -1 EUR
Drinking a 0.5L
in a club or cafe is 4.5-6 EUR
in local bodega is 2-3 EUR
Attractions is a broad term, but assume around 10 EUR for museum tickets.
A meal at a motorway rest stop is 6-10 EUR
A hotdog at an AMAZING danish hotdog stand is 3 EUR ( don't miss this)
10 oranges/apple/pears for 3 EUR in most supermarkets
Prices in Sweden and Norway are comparable. 10-20 % cheaper in sweden and 10-20% more expensive in Norway.
Alcohol is very expensive in Sweden and Norway.
Brigde Tolls in Denmark
Storebælt (between Fyn and Sjælland)14 EUR oneway for a motorcycle.
Øresund ( Denmark - Sweden) is 15-17 EUR one way for a motorcycle.
Let me know if you got more questions