Detect Image Target via Hololens Camera

Hi guys,

Currently I am quite confuse about the way vuforia detect Image Target.

Take an example below:

I would like to create an AR App for hololens, which can show informations about some specific thing (AR like) in the realworld, which is a 3D Object (eg. a big house) when i look at it.

for example when i use the hololens to view a house. i would like to see the information about that house like size, building time etc...

So like from the basic tutorial example from vuforia (https://assetstore.unity.com/packages/templates/packs/vuforia-core-samples-99026), I would say:

Firstly I need to define a 3d model target of that house via model target generator or maybe Object Scanner???. then use it as 3D Model Target in Unity and when the  hololens camera detected the model target, i can start to show the specific information (eg. size, building time, etc...).

For me the house are like the Image Target which is similar to the cards from vuforia samples (but in 3D so it has to be model target) and the information which need to be show  will be in ar view.

How do I suppose to do that ? From my understanding I have to save the House as Target (which one to fulfill the job, i still cant figure out) in vufodia target manager.

I am searching for the right way to realize. Currently I know Model Target Generator and Object Scanning. I dont know if I should use them to do my work .

One more question would be.

Do i have to define the Target manually with vuforia target manager everytime when i want to add a new target to my application, which need to be detected or can I do that dynamically via programming. 

Thanks