Palmolive, hot water, a scouring pad and a little bit of elbow grease were all I needed to remove years of grease and grime.
If you want to preserve the current paint or finish, then I wouldn’t recommend using the same technique. The scouring pad removed a layer of paint with the unwanted grime, but that just saves me time and effort. I can now skip the sanding step and jump straight to the priming step.
The only challenge lies in how to keep Elly occupied with her washable paints while I paint over all the avocado green. Wish me luck.