Rentals Under LLCs?

[Jay Audi]

Hey everyone, 
I am just starting out in the real estate investment world: I have a primarily residence that I rent out 1 bedroom of and I am looking to purchase a Duplex in soon. 

The deal I am looking at right now is actually two properties in one. As I purchase this second property, should I put that property under and LLC? In your experiences, should each property have their own LLCs, or can just one LLC with all the properties under it suffice? Additionally, what are your thoughts on putting the primary residence under and LLC as well?

Thank you for any additional advice you can give!