Cut an existing 3d model into 4 different parts

Hello, I'm looking to cut a pre-existing 3d model into 4 different parts. The model can be found in the link below. I have also uploaded a powerpoint that shows how exactly this needs to be cut. In the end, I need 4 pieces that are 4inch by 6inch in STL file format. The base will also need to be about 3mm thick. Any building that are cut in half in the slides with red boxes can be removed. There is no need to cut any buildings in half. My goal is to 3d print this. The link to the model: [login to view URL]