The number of users you can invite depends on your subscription tier. Starter allows 3 users, Pro allows 10 users, and Agency allows up to 50 users per store. Each user you invite can be assigned one of four permission levels - Owner, Admin, Editor, or Viewer - giving you fine-grained control over who can do what within your store.
For most brands and agencies, these limits provide plenty of room for collaboration. If you need more users than your current tier allows, you can upgrade at any time through your Auware dashboard or through the Shopify Billing flow.