For me that's one reason to have sa as the DB owner. So that I won't have any cases where logins have more rights than their assigned permissions state.

Ownership doesn't require logging in. It's just about what security principal is associated with the job (or DB, or other things that can be owned)

Have you tried?

Or tried a search? https://www.sqlskills.com/blogs/paul/disaster-recovery-101-backing-up-the-tail-of-the-log/

Restore from backups (full + log should get you back up with no data loss)

Is this a virtual machine, or physical?

If it's virtual,  then you can assign fewer cores to it in the VM configuration.
If it's physical though, short of removing...

You can have error handling and transactions to roll back partial operations and still have it email you.

There's no magic value for PLE that's good.

In general, you want it as high as possible. Consider that it's a measure of how much churn there is in...

Use the ALTER DATABASE ... MODIFY FILE option for moving the files, and note that once you take the DB offline you need to move the files manually, SQL won't...

Yup. Normal behaviour. Most errors terminate the statement, not the batch.

If that's not what you want, you need some error handling, and probably some transactions.
http://www.sqlinthewild.co.za/index.php/2011/05/17/on-transactions-errors-and-rollbacks/

In both places where that appears, you need a WITH added (or, probably better to take the index hint out)

It's got to read every single page in that 700GB database, and do a bunch of checks to make sure all the pages are correct, all the DB structures are...