Actually they don't smell like anything.
If they're not washed, they smell pleasantly of fox musk. And lately I'm only freezing them repeatedly to preserve the foxy smell.
And if they are gutted, they smell a bit meaty. A hot bath then will also give off a bit of a soup smell, but it's a good idea to stitch them up before cause the fur will get oily if you don't.
Repeated freezing really does a weird thing on how they degrade, making the process going in reverse (skin -> inside, rather than digestive system -> muscles -> skin) with the skin going bad first and the meat staying good. The fur starts slipping way
before it starts to stink though, so if that happens anywhere, immediate action needs to be taken. A small patch may be fixable. If you wash the whole thing and no further areas fall off, you got lucky. Just dry it properly and it'll stay good. Applying alcohol every once in a while to mouth, nose, dick, balls, underbelly and butt area are a good idea (thinner skin = more moisture from underneath, moisture -> slipping fur).
Fur can also fall off if you accidentally wash it with burning hot water. Basically if it's too hot to touch, it's too hot for a fox.
The more you know.