One thing you need to remember about code is it only applies at the time the home was built. You can't know what code was in any given jurisdiction time or place. Codes change, some areas adopt, some don't. You can't hold a home built in 1978 to 2018 codes. There are going to be multiple upgrades done on those homes. What code applied at that time? When was each code adopted and applicable?

I can't walk into a 1965 built home and expect to find grounded outlets and modern wiring. That's why I don't quote code. We have 30 different jurisdictions in our region and every one of them adopt different codes and enforce differently. When you start quoting code you are implying you are a code expert. I know very few people who can make that claim.