What are the primary goals of creating a building model? Who are the key stakeholders?

• What do they need?

The primary goal of creating a building model is to better illustrate the complex design in a simple way where constructers can quickly understand what they are supposed to do with details.

• What do they care about most?

I guess they will really care about the details, such as dimensions, materials, and construction technology

Many door and window manufacturers provide Revit families for doors and windows that you can specify for your building design.

• What is the advantage to manufacturers for providing these families? (it's not free to create and provide them...)

Since Revit is a very popular software in BIM, providing Revit families for their products is a good opportunity for advertising. Even though it's not free to create the models, the manufacturers get a very good chance to let more people know and use their products. They are kind of writing the code for this field.

• What is the benefit to you as the designer of using these manufacturer-provided families? Is there an advantage to using them versus the families provided in the Revit library?

Using these given families first save my time from establishing them by myself. The Revit provided families are limited in style and at this time I will prefer to search for manufacturer-provided families to better present my design.

What are the advantages of getting the Revit component families (for furniture, equipment, and fittings) directly from the manufacturer versus from an online sharing website like RevitCity.com?

Compared with online sharing website, Revit component families are more commonly accepted among engineering field. Therefore, using the component families can guarantee the consistency between engineers, manufacturers, and constructers. It can also decrease misunderstanding or communication problems.