Moving to a country at the end of the world could have very good sides, but also some less good ones. Iceland is the perfect country to stay in if you are not a big fan of the warm weather and busy places.
During the winter time (mostly September to April) the sun is shining in the sky only for few hours and in December you will get only few hours of daylight. But see the bright part..more darkness, more chances to see the northern lights!
In the winter, the winds and the precipitation might be extreme, which means that some days you can barely walk and others everywhere will be extremly slippery. The temperature does not go very low, but the winds make everything more intense!
Also, when it comes to the summer, you have chances not to get the summer at all. This year, in 2018, the weather in Reykjavik was more similar to November than to June or July. There was a lot of rain and many, many cloudy days.
Icelandic is a difficult language. Even if it might sound interesting and it would eventually make sense to you, it is very hard to become fluent. The good part is that mostly everybody speaks very good English!
The prices in Reykjavik are way higher than anywhere else in Europe, which makes the life a little bit more difficult. If you choose to have your meals outside, you should expect to have the bill around 8000isk/person. In case you like to cook, things might be a little bit brighter and you could spend maybe 40 000 isk/month for one person.
If you talk with anybody that does not own a house here in Reykjavik, they will tell you how hard it is to find a place to rent and if you do find one, you will pay most of your incomings on it. An apartment in Reykjavik starts somewhere at 200k isk/month, but you might still need to use the public transportation.
The food in Iceland will make you miss your vegetables and fruits from home. You can find some of them very good, but some others maybe less tasty than what you are used with. If you are a fish or a lamb lover, it means that as soon as you arrive in Iceland, you will be in a food paradise as these products are AMAZING.