New lease when buying with existing tenants

[Tommy Andrade]

Hello. 

Im looking to buy my first 3unit home. Its currently fully rented. One of the tenats expressed her intentions to move out if a new owner wants to occupy a unit. Im planning on letting her stay 60 days after the possible closing day hoping everything goes alright with purchase.

My question is can i honor and endorse current leases? like put my name on each sheet and add a note that states who i am... Just an idea. 

Or is it legal to use current leases content just changing my name and dates, print it out and have them signed?