1. I have to create the other 4 users as a subaccount of my BitBucket account. All repositories (projects) I create will be limited to these 4 subaccounts
2. I can add any existing BitBucket user account for collaboration on all my repositories, implying that I cannot have an account (a,b,c,d) for one repository and account (e,f,g,h) for another repository. All repositories must use the same BitBucket user accounts I have added for collaboration to my account.
3. Same as 1, but you can have different sets of subaccounts of users created for each repository.
4. Same as 2, but you can collaborate with different sets of users per repository
If it is a mixture of any of the above let me know.
Thanks in advance