This video may be a good start: https://youtu.be/XfRvXImRAi4

Not sure where you are in the world but in the UK I use Dettol, an antiseptic disinfectant, the old version that is an amber colour.  Works perfectly for both metal and plastic and the advantage is that it is really easy to get hold of and doesn’t have any unpleasant fumes.  I keep mine in a jam jar, chuck the minis in, leave for a week or two, remove the minis and gently scrub off the paint residue with a nail brush or similar.  If there are still sections of paint that are stuck then put it back in the jam jar and repeat in a week or two.  Easy.  Dettol remains active for a very long time, the stuff in my jar is well over a year old and is still going strong.

Yep I definitely agree dettol works extremely well. I’ve stripped PVC, HIPs plastic and metal mini’s with it and it’s not failed me yet.

Just invest in some disposable gloves and cheap tooth brushes (for scrubbing the mini’s).

Dettol works well but I’ve found that it leaves miniatures (especially plastic ones) smelling which can last ages.

I’ve found that (I’m in the UK by the way) Paint stripper from Wilkinsons is great, it’s quite harsh stuff, but not as bad as Nitromors (which is just awful).
I use 3 takeaway tubs, one with Wilko stripper, then rinse off in a degreaser (I use “elbow grease” which you can find in most cheap shops), then a final rinse in water. it’s a fairly quick process.

Plastic, metal and resin minis can all be stripped with the wilko stripper, I only leave them in for around 30mins, then a quick scrub with a toothbrush, mainly to get the worst of the goopy stripper off,
then a dip in the degreaser and another good scrub with the toothbrush,
final rinse in the water with more scrubbing.

Job done 😀

If you have access to an ultrasonic cleaners (Used for cleaning jewellery and airbrushes) I can recommend putting them through a few cycles in one, once you have done all the other cleaning.  It can get out the loose but impossible to scrub parts.

I use Dettol.  I dunked some 25+ year old painted metal minis at the weekend.  Left them in for about 30 hours and they are looking as new right now.  One huge warning with Dettol if anyone tries it.  Never add water.  Never rinse your scrubbing brush (Toothbrush) and then put it in the Dettol.  Never wash the model and add it back to the Dettol.  While I have never made this mistake, I hear it turns everything in to a big black sticky mess.  It is safe to wash your minis in water once you are done with the Dettol though.