When I had a similar situation with 43 different properties with the accompanying improvements, I created the new asset information and then deleted the old one.  Since the old one was valid for a part of the current year, I did not remove it until the following year.  The biggest danger was being certain to remove all the outdated assets the following year. Watch out for community property situations as opposed to non community property states.  Like you there was a big search for an easier way but I certainly couldn't find it.