OpenKJ and its various projects are managed and maintained by a single person, who also both has a full time job and is a karaoke host. This means that securing your account information, which is incredibly important, would only be one among many competing priorities. Google, on the other hand, has an entire department of experts dedicated solely to security.
OpenKJ Songbook uses chargebee to handle subscriptions and payment info. They are PCI DSS Level 1 compliant, and your information is always transmitted to them via encrypted HTTPS connections. The only part of your credit card number even visible to OpenKJ is the last 4 digits.
You will not be charged anything until your free trial period expires. If you cancel any time during your free trial, you will not be charged anything. Once your free trial expires, you will be charged for your first month and then automatically charged every month after that.
No, the song database is account wide. All venues will use the same song data.
No, currently we are only offering subscriptions/services that are intended for use by a single KJ who has one system or uses the same song library on all of their systems. Premium multi-op/multi-rig accounts are in the works, which will allow multiple concurrent venues to accept requests at the same time and which will have venue specific song databases. For now, you could still use the service, but would need to use a separate subscription for each venue or KJ.
Songbook shares a database with the free OpenKJ Karaoke Database site for download vendor song data. The simplest method would be to keep a window open to that site, and when a request comes through that's not already in your library, search db site and click the link to the song on the vendor's website.