Do I need a multisite or single site set up?

Hi. I'm setting up a new social enterprise- basically a 50+ membership service.

We want to have a web platform for members to:

1. buy memberships
2. create profile & engage with other members
3. See events & buy tickets
4. book practical help services
5. Get deals from local businesses.

I'm used to creating ok WP sites and have found plugins to help me...

For example (& all wpmudev at the moment too!)

1. membership plugin
2. use buddypress
3. Event +
4. Appointments
5. Directory (listings)

Do all these plugins work together?

Should I create a multisite set up so I can split up the functions more clearly?

I hope that makes some sense and look forward to your advice

Thanks

Graham