No crank no start

Follow the smaller positive battery wire to the under-hood fuse box. Clean and/or tighten that nut. This has been a common problem on all car brands.

Also follow the smaller negative battery wire to the body and be sure that one isn't loose or rusted.

Same applies if battery and fuse box both in the trunk?

I've never gone searching there, but you'll get the same symptom if either battery cable is loose or badly corroded. The loose cable at the under-hood fuse box has been so common that we typically snug them down at every oil change on customers' vehicles.

If you want to verify if I'm sending you to the right place, you can do this with a test light. Touch it to the stud on the fuse box. You'll see 12 volts there. No, have a helper try to crank the engine. If the connection is the problem, the test light will turn off. While it's still in that defective condition, move the test light to the terminal that's crimped onto the end of that cable and you'll see 12 volts is still there.

It's not uncommon to see a spark where that terminal is bolted to the stud when a helper tries to crank the engine. That's proof that connection needs to be tightened.