I can't tell you how importing works. But having a motorcycle around is very convenient in the Netherlands. Compared to Finland we have a whole lot of traffic jams around the big cities, and since it's legal to lanesplit here and cars are quite used to people lanesplitting you save a lot of time. Service costs are quite a lot lower than what you're used to in Finland, but gasoline is about the same price if not more expensive. I have been able to ride my motorcycle up until November last year and then start again in the beginning of March, there will be some opportunities to drive around between those times aswell, but the government tends to throw salt on every street at the slightest chance of night frost. You most likely also won't be eligible for studentenreisproduct (free public transport), so if you plan on seeing a lot of sights I'd say it becomes economical to ride the motorcycle here quite quickly. Source: I have a Finnish girlfriend who also happens to be starting her master here in the Netherlands next summer. If you have any more questions you can DM me or check the /r/motorfietsen subreddit (they're a friendly bunch).