Yea automotive brake fluid I use it on my 40k models when I buy some pre painted ones on ebay or something. Just get a generic brake nothing expensive. Pour it in a cup and the model in. Let it sit for about 20-30min and take a tooth brush and scrub the paint off and loosens glue too. You can try acetone on the models if you want to get the glue off just dont use too much and once youre done let it fully dry and harden back up bc it will go soft of you. It should do it quicker being hard plastic rather than rubber. Again never do on casted resin models either of these techniques your model will be destroyed. You can also go to a local hobby store and there is actual glue releaser, if they do not have it they should be able to order it.
I think I payed like $3 for a cheap bottle of brake fluid, $5-$7 for acetone, and the glue releaser is like $5-8. But its how much you are willing to work on it. Brake fluid is cheap by just loosens, Acetone will removes but possibility of damaging models and a little more than brake fluid and The glue releaser will remove the glue but kinda expensive for how much u get.