In reply to Miroslav Glavić.

I find it a bit ridiculous that a consultant would charge to update a site when the update consists of nothing more than bug fixes. I think as a consultant, you should empower and educate your clients on how the update system works. Then, if they experience a problem after an update, that's when they come find you and pay you to fix it, though those times should be rare.

Also, Gabriel posted the code you add to your wp-config file which will disable auto updates all together.