Lease renewal question

[Harry M.]

Hey Folks - quick question for you.
We recently purchased a duplex, already with tenants.
The leases are up soon. My question is about how to handle the renewals:

1) Create a new lease.
2) Create an addendum to the existing lease, saying that the agreement between old owner and tenant is now is now between us and tenant (any tips on language also much appreciated).

The content of the old lease is ok, so I'm mostly interested if there is any advantage of one over the other.

Thanks in advance for any replies.