Lease contract when purchasing a property with existing tenants

[Steve Penney]

I am getting ready to close on a duplex with one existing tenant who is about four months into a one year lease.  I understand that the lease comes with the property but I am assuming that a new lease will have to be written and signed to reflect the change of ownership.  My question is can I use my own standard lease form modified to reflect the major elements of the existing lease (assuming that the tenant is in agreement) or would I be better advised to keep the exact wording of the existing lease and just change the relevant names and dates?