But quite reasonable compared to the rest of Scandinavia!
Contrary to a popular misconception, Finland is NOT part of Scandinavia.
They don't share the German cultural or linguistic heritage, and Finnish is neither related to nor mutually intelligible to speakers of Danish, Swedish, Norwegian and Icelandic.
All of which are regarded by linguists as mutually intelligible, although speakers of them might disagree, at least until they've had a few vodkas.
Foreign usage of Scandinavia does sometimes mistakenly include Finland, perhaps because it was annexed by Sweden from the late 12th century until 1809.
However you're right to observe that it is less expensive than some other Nordic countries, especially Norway (ouch!).
The Finnair bus is quite comfortable and has good free wifi. I'm fairly sure it was free - either because I was OWE or because I had flown in J on Finnair.
I caught it from the airport to the city.
However I was unable to find the stand at the city train station to catch it back to the airport, so with time running out I caught a taxi instead.
You might want to research this in advance if you will be relying on it for your departure.