Thank you @Carl and @Critter-3
I have been taking depreciation. I'm not sure how I came to the figure for its value 16 years ago, but the problem we have is that while we have spent a lot on our house and significantly increased its value (it literally hadn't had any work done on it since the 1940's) we have done nothing at all (other than maintenance) to the apartment and if anything that building is worth less now than when we bought it.
I think I'm going to go with @Mike9241 's suggestion and get the apartment appraised separately and then use that as my current value for it.
I really appreciate your help and input. Thanks again!
