Most of what you'll find on-line are not spec scripts, but production scripts which have been scene numbered or otherwise slightly altered by directors and ADs to facilitate shooting. Additionally, if you're reading a script of a writer/director, then you need to understand it might as well have been written in crayon as it was never going to be a spec sale. These can legitimately use all sorts of cheats a spec script might easily be rejected for.
My advise would be to check out the book, "The Hollywood Standard" (second edition) by Christopher Riley. It details all the minutia of format in dealing with pretty much every circumstance you can possibly think of.
After you've read it, you'll get a much better understanding of what is considered basic formatting. More importantly, you'll also gain a bit of understanding as to why certain elements are the way they are, something you'd never get just looking at a sample page. For instance, why you'd use a parenthetical comment under a character's name, but never in scene description. Why you'd UPPER CASE some items in scene description, but not others. Follow that and nobody will ever complain.
Give it a look. I know it's available on Amazon. You don't have to pay full price either.