The example, the car's keys may run into trouble with strict grammar rules which restrict ownership to only living things. In this case, a car cannot own keys. To circumvent this problem, some writers would phrase it as the car doors, where the words car and doors are taken together as a noun. Likewise, it may be awkward to say the table's legs. Instead, we would say the table legs are broken, for example. So far, so good, but what about lamp's bulb. I have no trouble with that although strict grammarians may insist on saying the bulb of the lamp.
The use of the apostrophe with proper nouns such as Nora's husband presents no difficulty. However, traditionalists may argue that James' skis would be out of sync with the traditional rule that requires the letter 's' after the apostrophe for names that end with 's' as in James's skis. The same rule says that it's not necessary to have the letter 's' for Biblical or classical names as in Jesus' teachings and Hippocrates' Oath. The trend now ignores this traditional rule and it's common to see writers writing Jess' speech alongside Jesus' teachings. I think Jesus wouldn't object to that.