Sharepoint set up for small NFP business

We are a small not-for-profit independent kindergarten and require the setup of a Sharepoint system. The main purpose of setting up the Sharepoint system is for document management and collaboration. We have no specific customizations or features, and are open to suggestions from experts. The number of users accessing the Sharepoint environment will be between 10 and 50. We need an expert to help us get set up with a Sharepoint system that meets our needs.

We need:
document management
different areas assessable by different users eg. committee, admin, HR
also interested in streamlining document approval processes - eg. director approving timesheets or purchases without having to print, sign, scan etc.