I totally understand where some of you are coming from. However, when it comes to an issue like being double charged, wouldn't it make sense to approach us first? We aren't thieves trying to con our users into signing up for multiple packages so we can steal your money. I've yet to deny a user a refund for ANY reason.
Again, paypal has some pretty big limitations, a ton of our users have a separate paypal email address than they do for SEscout, there really isn't a way for us to know if you are setting up a second subscription then to do a manual check for it. We've put up measures to help insure that this doesn't happen (for instance the disclaimer on both the "upgrades page" and the message you get when you return from upgrading on paypal). The easiest way around this is for us to simply use a credit card processor, but with SEO's being notoriously private as they typically are, I can see that being a big barrier of entry for a lot of people.