fixing up a 1920 row home - wood paneling everywhere - Advise before I go in?
Surface is surface. Paneling is surface. Surface is the cheapest and easiest of home repair.

Tearing it down can do no harm. You will almost certainly need to install a new surface material on any wall you strip, but drywall is cheap and fairly easy. If you are going to tile (e.g. in the bathroom), you need a better base than cheap woodish paneling.

Also, it gives you a chance to find any hidden problems. Better address them now than after you have decorated.