To the above, I’d add it also depends on where the mold seam & finger prints are located.
Often MS gets missed on a tow pinnacle or hook or tool handle. Typically, that’s an easy fix with flicking a #15 scalpel blade over the mold seam perpendicular to the mold seam. Normally far less invasive than sanding in my experience. Occasionally rehash of whole model could be needed… With a high quality paint like Floquil or Tamiya a very light dry brush across the exposed plastic works for repaint without needing a Re-prime.
Finger prints are a little more challenging. A very slow and light touch with #1000 to #1,500 grit sand paper or #sanding stick can,work wonders. It is possible in some cases to remove finger print in upper layer of paint without cutting through primer/black coat to plastic. If the print occured in the primer/base coat likely will have to go to plastic to get rid of it.
The #1,000 to #1,500 sanding paper/stick can also be used to remove bits of over spray in two of more color camo schemes or to distress paint.
In any case, be sure to blow all of the accumilated debris, fuzz, hair & dust off of model with airbrush before any paint application by dry brush, brush or air brush. otherwise repairs can become a bigger issue than the original problems.
Of course, sometimes full scale repair is needed and sanding to plastic, reprise and repaint is the only real fix.
Wish you the best with paint repairs.