A typical business would need to generate an additional $1,000 - $2,000 a month of digital printing sales alone just to make the lease payment on a decent printer alone. The problem is you really need a lot more than the printer alone to make it worth the effort and, like the others said, $30K is just a drop in the bucket.
On the low end, you should also spend a lot on the following:
$3,000 for a high performance computer
$4,000 for software - Corel & Adobe Suites, RIP software
$5,000 for a good laminator
$1,500 for training
$1,500 for color calibration hardware and software
$2,000 for media and laminate
$ 500 for misc supplies
$ 500 for production tables
So, besides the printer, we're at an additional $18k+ before the cost of acquiring or building the appropriate dust free, environmentally controlled area all the equipment should reside in.
I'm sure if you do the math, a more reaistic number to get into digital printing would be somewhere between $50,000 to $75,000 when it's all said and done - figuring in overhead and other costs related to the acquisition.
Spending this kind of money up front will get you where you can comfortably sell printing without the worry of being able to produce it, because if you can not produce it without issues - in a timely manner, your clients will go elsewhere.
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