Thank you for the lesson. Moved around a lot when in school. Inconsistency is probably why I had trouble. I thought it was the teachers. Then I find out the rules are in conflict. And the foundation crumbled.Depends on the style guide. I prefer to use British standards because it makes more sense. If you're quoting someone, put the period or other punctuation mark where it was in the quote, but leave it outside if it's being added. Americans shove everything inside and it looks cluttered.
Some use single quotes for emphasis and double for quotations. Some use single for both, or double for both. It gets confusing. Basically, do whatever you want because it's acceptable in some style guide somewhere, but do it consistently.
I had no clue you are a headhunter. Interesting the things we learn. I find the bear skulls to be massive and massively interesting.