Here is a tip when trying out a "free" trial period on a site. Some banks offer a alternate credit card number that you can decide how much can be billed, when the card will expire and you can control when to stop recurring charges anytime. It works like a credit card online and if you want to stop payment simply delete the card or change the amount allowed to zero. I use "Shopsafe" and it has worked very well to prevent additional charges if I try to cancel a membership or trial access on various sites.