Access to external users

Hello,

I am working for a non profit organization and ours is open source code. So we have few questions regarding security and access to the testing artifacts within Jira/Zephyr. 

1. Are there any aspects of the testing that can be made openly available to external users, here external means  users outside the project/not part of the project.

2. Is there a way to make Testing data accessible to most appropriate users only? Not to all jira users?

3. If there is any increase in number of users, how will it affect the pricing over the period of time?

Looking forward to hear from you.

Thanks & Regards,

Ramya