If money is the most important factor, well, this project might not be exactly, what you are looking for.
But you also state you would rather have an OSS-computer in your hands with phone capabilities than a pure phone, that is the N900 and, may be, if we are lucky, the Neo900 as well.

My expectation regarding openness of Jolla is low. They were Nokia people and their track record to bring a true OSS-phone to the market is obvious in the struggle to update Maemo to more modern Debian versions.