Personal view is make life easy for buyers – I rarely password protect anything.
Instead:
* Just make sure the pages aren’t able to be easily found. In WordPress (the Search Exclude plugin does that), outside WordPress don’t include them in a site map or a directory that can just be browsed (make sure there’s an index page in each directory)
* In WordPress, exclude from the list of pages if they’re a page, not a post (Exclude Pages from Navigation plugin). Outside WordPress, you probably have control over site navigation.
* Set to NoIndex NoFollow (Yoast offers that in WordPress, your HTML editor will allow you to add it outside WordPress)
* Untick any sharing button options if appropriate.
* Edit the page name from any auto-suggested one if it looks too easy to guess and if I’m feeling extra paranoid
Most buyers aren’t crooks!