The three Aston Martin DB5's were used rather destructively in the film to avoid the expense (and tragedy) of blowing up a real DB5. According to CNET, one of the surviving models was sold at auction for near USD $100,000.
The models were produced on a VoxelJet 3D printer, well known for one specific advantage: Hugeness! We're not sure which VoxelJet was used by 007's team, but the VoxelJet 4000 has a build volume of 4 x 2 x 1 meters!
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