If you are missing a building we have a search tool on the neighbor bar.
Now you can just click on the House icon and search for your building or decor.
This will show you how many you have in your city and storage.
You click on the SHOW button to see where it is in your city.
Just click on the Left and Right arrows for it to take you to each one.
Works for your decor as well.
Just type in what you are looking for and then you can scroll down until you find it.