CAD files (specifically .dwg files) are ubiquitous in the design/build world. So what happens when you bring those CAD files into SketchUp?
Source: How to import CAD files in SketchUp
Here’s my list of top 7 free CAD programs and online tools every CAD user should know. Convert, edit, import and adapt your CAD models.
Source: 7 Must-Have Free CAD Programs and Online Tools – Bricsys CAD Blog