It really is a learning process! There are a few things I won't feed - pig feet for the reasons mentioned above, actually. Venison (whole) because a: those bones break into scary shards and b: wild animals harbor so many pathogens and parasites, and I've had some issues with paint-peeling gas and dire rear
with feeding wild critters. I've bought whole ground venison, though. And turkey, because those birds are so genetically engineered they are freaks of nature and not "natural." The only time in all these years I have ever seen bone pieces in my dogs' poops was after turkey and that scares me, so bone-in turkey is a no-go. I do get them turkey gizzards and tails (which are mostly gristle and fat, but cheap.) Turkey necks are cheap too but look like perfect large-dog choking hazards to me so again, no. I have bought the pig testicles a few times, they're sort of jelly-like but the dogs ate them.
I buy up whole chickens when they're on sale and whack them into the appropriate size for doggie meals. That's so easy and inexpensive I wouldn't pay for whole ground. For a few years I had a great source of pasture-raised chickens for .99/lb but sadly they lost their farm during the recession.
I will say in 16 years of feeding raw, I've only had one choking incident - a Rottweiler puppy I was taking to work who swallowed the knot off of the client's dog's rawhide bone. Scared the crap out of me but the pup was OK.