Treat your CV as a product and make sure its client ready because typos is the one thing that makes it easier for HR to toss your CV / Cover Letter.

You don't want to make it easy for them. Heck, you want to do everything in your power to take yourself out of the equation - outsource that decision making process to them. 

But if you have typos in your CV / Cover Letter, you do exactly the opposite. You make it easier for them to toss you out.