I spoke to Jesper this morning and Janne this evening. As per my previous post, we're going to do a metal roof. Janne will order the roof panels, I'll carry them up to the house when we're there in October, and Jesper will come and do the installation later in the month.
Jesper will need a few pieces of wood trim and other accessories. He'll send me an email with all of his requirements, and Janne will place the whole order to be sent to the midsummer dock.
If all goes well, I'll have a metal roof by Halloween, at a cost near my original budget of 25,000kr.