It depends really. if you're selling a lot and come out with new products often, if might be worth it, but if you're not moving a lot of product, probably easier to just find a print company to do them for you. You should also take into account, the price of the printer and the price of the ink and paper.
I used to do most of my own printing from home. I had a big fancy wide format printer that cost about $1200 and each ink cartridge was about $65, and it took 9 cartridges. I got around the steep price of ink by buying 3rd party ink with "hacked" cartridges that were refillable. The cheap ink made it worth it for a while, but you'll quickly find that printers are jerks and issues arise often, especially with 3rd party ink. It involves a lot of internal printer cleaning as well as getting ink all over the place, every time you need to refill a cartridge, not to mention if your expensive printer breaks and you need to take it to a repair shop, you've voided your warranty by using a refillable ink system.
Of course this is mostly all for more expensive printers. If you're planing to buy a smaller printer that has relatively cheap ink it might be much more manageable. When it breaks, it's much easier to just buy a new printer. If you go through a company, like catprint for example, you can still get fairly cheap prints done without all the hassle of messing with a printer though. I'd suggest doing an order from a company first and comparing your profits to see, before committing to buying a printer.