Hello, The cost of the cylinder I believe is under one hundred dollars. Depending on if the cylinder can be put into the correct position for removal would depend on the cost. If you look closely at it you will see little hole along the perimeter of the inner ring. this is where you put a long tool to release the cylinder in position one. However, if the cylinder is disconnected at the wrong position it may be required to replace the housing also which would be a few hours labor compared to like one hour or less. Removal is tricky as is installation. You want the cylinder in position One, one click back from where you are. One thing you may try just to get it functional for now is inserting the key and tapping the end of it lightly with a small hammer to try to re-engage the cylinder. I have been lucky with this from time to time. So in short your looking at two to five hundred dollars. Thank-you and please Accept. Best regards Jacob.
BMW Technician
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