Hands down, voxeljet (NYSE:VJET) is the most expensive 3-D printing stock around. At current levels, this industrial 3-D printing company is trading at around 25 times 2014 expected sales -- well above its peers. However, price isn't the only issue with voxeljet.

Recently, the company burned through about $13.7 million, or 20% of its IPO proceeds, to purchase its German headquarters and expand the service center on site. In the year prior, the company spent roughly $400,000 renting the same property. This could be a huge warning sign that management doesn't know how to efficiently deploy capital, which could lead to non-accretive equity raises down the road. As an investor, a management team that doesn't know how to effectively deploy capital is probably best to be avoided.

In the following video, 3-D printing analyst Steve Heller makes a case for why voxeljet shouldn't be part of your portfolio.

Fool contributor Steve Heller owns shares of 3D Systems and ExOne. The Motley Fool recommends 3D Systems, ExOne, and Stratasys. The Motley Fool owns shares of 3D Systems, ExOne, and Stratasys and has the following options: short January 2014 $20 puts on 3D Systems. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.