Easy way to tell!
Before we dive right into the hidden historical features or ways in which you can tell you have them, but they are very well preserved, so you could never tell, we have to talk about the easiest ways in which you can verify the status of your home. It can be as easy as just checking in with your local State Historic Preservation Office (SHPO). Every state should have such an office, and they should be able to tell you if your house has been there for a long time, along with any paperwork that has been filed for that address over time.
What’s more, if you discover certain features but are not sure yet how historically accurate they are, you can also go to the SHPO in your office or write to them with pictures and make inquiries about your property. They will also be able to check with the National and even State Register of Historic Places, and you will be able to get a definite response pretty soon.
If you do not want to go through all that hassle, it is also a good idea to check for pictures of the area where you live and documents on the Library of Congress website. They have run a Historic American Buildings Survey (HABS), and their database is extensive, so you will be able to search for the information you need.