One user case that I've seen a lot of interest for recently is early stage estimates on buildings, this is quite easily possible using floors or potentially other areas from an early mass model.
I've seen people mostly using resources to get additional items into the take-off that may not be modelled like skirting boards, such as fittings or the layers in a wall like insulation, brick, blocks and wall ties. Some people however have used 'Count' as a way to show costs associated with an item. For the purpose of an early cost estimate you could create a number of estimates based on building type, trade type, or work package type and save this in a catalogue. There seems to be lots of cost estimates available per square meter (or feet for my American friends), from industry bodies and internally in most firms so you can use these to create catalogues. There is a blog post showing how to Use Catalogues in Navisworks Quantification, there is also a Navisworks Quantification Catalog Creation template available to speed some of this process up.
In the proof of concept example below we've added a cost of £1300 per square meter to a Supermarket and used that cost as a 'PrimaryQuantity' so it's easily referenced. We've added costs for MEP fitout and things like Security and AV equipment.
As a next step you'll need to make sure you pull the area across from the model or drawings. As this can come from a range of file formats or you may be looking for a specific floor or net or gross are you may need to head to the Property Mapping button on the Item Catalog and select the right property which shows the area for your mass or early stage model.
You can then select the floors in the mass model, either as a Search set or using the Select Same button and drag and drop into the Quantification Panel. You can then go to the select a number of building uses, or required items for a quick rough cost estimate based on the model or drawings.
You can Download a sample of this catalogue that SHOULD NOT BE USED FOR COMMERCIAL PURPOSES, but will give you an idea of the workflow should you wish to pursue it further.