Distressed Asset Investing

All you folks that look at distressed assets vs. corporate securities - how do you value/analyze opportunities? Like when you’re buying a bunch of NPLs or distressed shipping/RE assets or like subrogration claims even (like Baupost loves to play in). I’m not sure if there’s any primers on this, but how do you approach these opportunities? Given the market is opaque and no bid/asks you can see for where the market currently is, how do you focus on valuing these assets intrinsically - keeping in mind the more assumptions you make, you run the potential of “garbage in garbage out” (same danger with like DCFs).