I put my motorbike on the ferry, from Korea to Russia. It cost be about $250USD. I know that they do carry cars and trucks all the time, but i am not sure how much they cost.
After I entered Russia (three months ago) i heard a small roumour that they are stopping temporary imports into Korea - you may want to check up on this. I used Wendy Choi to do my paper work. As i was short of time and needed to catch the boat in a hurry. If you give her an email, im am sure she will answer all your questions.
For more information on my adventures, please visit either of the following: