How to plan SharePoint global and departmental sites?

Question

My company has 3 departments: HR, Finance, IT.

I have following windows groups:

1. Win_HR - contains all HR staff
2. Win_Finance - contains all finance staff
3. Win_IT - contains all IT staff
4. Win_allstaff - contains all staff

I have a need to upload documents into SharePoint such that Departmental files should be accessible only for the department staff. Certain documents must be accessible by all company staff.

What is the better approach to action this:

1. One site collection with 4 document libraries (common, finance, HR, IT). Permission to be broken at library level.

2. One site collection with 4 sites. Each site will have 1 document library. Permission to be broken at site or library level.

3. 4 site collections. Each with 1 document library. Permission to be broken at site level or document library level

4. Hub site

Answer 1

Your solutions are all feasible, the only thing to consider is the scale of use. The storage capacity and management level of the solution increase step by step. If your company is larger and will have more files to store later, it is recommended that you use a higher-level solution. If there are fewer, it is recommended to use a lower-level solution. In this way, it will be easier to manage later.

For your reference: https://learn.microsoft.com/en-us/office365/servicedescriptions/sharepoint-online-service-description/sharepoint-online-limits

https://support.microsoft.com/en-us/office/restrictions-and-limitations-in-onedrive-and-sharepoint-64883a5d-228e-48f5-b3d2-eb39e07630fa