I tired to import an AutoCAD 2D site plan into Revit. It seems pretty straight forward by going to File > Import/Link > CAD format to bring the CAD file into the model, until I realized the CAD site plan is located nowhere close to my model. Why is the CAD file living so far away from my model? Does Revit place the site plan randomly on the plan view or does it have an origin and the site plan is located correctly on the plan view?
The answer is YES! Revit does have an origin, if you try to draw a cross at the origin in AutoCAD and import the file into Revit (in the dialog box, check the box next to Link*, and under Positioning, select Auto – Origin to Origin), you will see where the origin is. Knowing the origin location is specially important if you are trying to import several levels of floor plans, site plan, etc., into the model.

Here are 2 useful articles if you want to learn more:
Link*
Link box checked- Your CAD file in your Revit model will be updated every time you make changes to it. You can view your entire list of imported cad files under File > Link Manager
Link box unchecked – The CAD file is inserted into the model instead of linked. All changes you made to the CAD file will not be updated. You will have to remove and reinsert the file for the updates.
I bet everyone asked the same question when they started to learn Revit – “What is a Family? When you start a new file, you have the option to choose from Project, Family, Titleblock and Annotation Symbol. It is easy to understand what Project, Titleblock and Annotation Symbol are without further explanation. But what is Family? Families are components you use to build your model, such as walls, windows, stairs, doors, etc. Each family can have multiple types, such as different size, materials, parameter variables, etc. Any change to a type is updated in every instance throughout the project. For example, when you change the window height of one of your window type, all the windows with the same window type are updated instantly. There is a list of predefined families that are shipped with your Revit software. However, you can also create your own family as follows:
- Create with your existing family – Select a family object in your model, e.g. window, and click on the Edit Family button on your tool bar. Modify and save as a new family.
- Create from Scratch – Go to File > New > Family to create your family from scratch. When you start a new family, a new window appears with a list of family templates for you to choose from. These templates are set up for creating different family models, so make sure to select the correct family template when creating your new family. For example, select the curtain wall panel.rft template to create a curtain wall panel family.
- Download families online – There are many resources on the internet where you can download a new family and bring it into your project. The two common places are Revit Web Content Library (Window > Recent Files, on the right hand column, click Revit Web Content Library, then click Revit Architecture Library) and RevitCity.