Finder not showing correct free space?
Finder does not take into account Time Machine's Local Snapshots. The storage space of these local snapshots will be given to files if necessary and therefore the space is not actually being consumed. Daisy Disk sees these files though and takes them into account when calculating the free space.

You can disable local snapshots by turning off Time Machine completely, or to retain Time Machine functionality without local snapshots you can run the following command:

sudo tmutil disablelocal