Hololens Help!

Hey all

I'm a software developer who has done some VR projects in Unity (SteamVR/Vive). Never done any AR/VR. I've been asked if I can create a Hololens app for calling out specific features / points of interest on a very large product that my company produces. They want to be able to walk around a room with this huge product (think 40+ feet long) and have the features be displayed. Here's the thing though, the product isn't made yet and so I won't have access to it. I also don't have access to the real space where the app will be used during development. The app needs to be ready when the product/space is.

I'm being asked for an answer/estimate immediatley so I don't have much time to research if this is even possible. Can I develop this with a dummy enviornment /product and somehow scan the product and room when I get there to map the labels to the correct locations? Overall, how hard or easy is this for someone with some existing Unity VR experience?

Thanks for letting me lean on your expertise!