To most manufacturers BIM means Autodesk REVIT, which you can buy if you've got a spare few grand. Sadly if you are using other 3D software your problem will be the highly proprietary file formats. One of my pet peeves!
Some provide models in proper file exchange formats such as Autodesk DXF, FBX or OBJ, but most do not.
There is a vast array of information available in BIM format, you just can't access it without REVIT. There are a few cheaper 3D programs that will import it but your still talking hundreds of pounds. There also many online sites that claim to convert all 3D formats, but don't. Blender, the open source 3D package I use has a paid add-on for BIM in alpha, no idea how good it is.
Basically unless you want to pay for proprietary software you are going to struggle.