Assuming that you will be selling your prints for a reasonable price and that the cost of consumables (ink/paper) are easily covered in your pricing, you should concentrate on printers using pigment based inks (Canon, Epson and HP all make printers for this market) and stick to OEM ink to give the optimum longevity for your prints.
This is an excellent subject worth much in-depth discussion for those who are serious about photos that will last like oil painting. Oil paintings will last for hundreds of years regardless there is fading or not. So thet are in a different class of prints. Photos should never be compared to oil paintings in terms of longevity.
Laser lightjet printing of photos is still the mainstream accepted professional photo printing practice. Inket printing (with pigmented ink) still mostly remain as a home hobby printing even for professionals although some tried to sell as a substitute of RA-4 prints. Cost remains very high and technically it is still far from ideal because of less ideal gamut of pigment ink. In shirt, it is relatively easy to optimize an inkjet print with dye based ink. When printing with pigmented ink one really should be aware that it will be a challenge to print equally well. In fact one should prepare for frustrations from being unable to print equally well. So it is my personal opinion to print with printers such as Canon pro9000 for the purposes of proofing before sending out the image for a professional lightjet print.
As Grandad35 said the cost of printing can be covered easily when the prints are sold. If I pay professional price for a photo I probably will not consider the same if the print is an inkjet print even printed with pigmented ink.