This 3D model was originally created with Sketchup 8 and then converted to all other 3D formats. Native format is .skp 3dsmax scene is 3ds Max 2016 version, rendered with Vray 3.00 Just a strange critter for your enjoyment. The basement is unfurnished so you can do what you want down there. This would be 4 concrete domes with connecting links, also concrete.