Interactive Architectural Walkthrough Unity

We have 6-7 floor layouts (autocad plans) that we need to design in 3ds max or maya in Low poly, so we can integrate it with unity3d for creating a interactive walkthrugh Customized coding is required as we want to create a beacon in the corner to allow the user to know his/her position as the main camera will always be first person. Buttons to directly go to specific floors. Its a simple project...quick worker needed. We want to work in Untiy. Modelling software is not important except it should be low poly.