General
Printers that produce photo-realistic images have 4 or 6 different ink colors, some with separate black ink cartridges. Resolutions vary from 300 to 2400 dpi, a cluster of these printer ink dots are required to produce a single pixel of a given color. More on Printer Ink Dot comparisons. For best printing quality, the source should be approximately 300 dpi. Multiply the print size by the dpi to determine how large a source image you need. For example, a 4x6 needs 6 x 300 dpi or 1800 pixels across. Smaller source images will make your printouts less sharp. The ink and paper you use make a huge difference in the quality and longevity of output.

Saving Money
You can buy ink cartridge refill kits that are much cheaper than buying the real thing. Check to see what your dealer/manufacturer has to say about using refill kits, it may cause warrantee and servicing problems.

Multiple Images
Printing multiple photos on a single 8.5 x 11 page can reduce costs, as good photographic-quality paper is expensive. You can arrange the images on a large work area yourself using an image editor, or use a program designed for that purpose. There are a number to choose from including HP Photo Finishing (free) and Photo Paper Saver (shareware), which is reviewed at Feather River Canyon News.

Printing Low Resolution Images
Expanding a small image before printing can sometimes improve the printout results. Another option is the PhotoShop plugin Genuine Fractals which expands an image using Fractal mathematics.

Preservation
Printouts are more delicate than photographic prints. To extend their life, Krylon Artist's Workable Fixatif is recommended to seal and protect your printouts. Using Acrylic instead of glass for framed photos will reduce fading due to UV Rays.

Selection
Nearly all of today's printers produce excellent results, take a file and give them a test drive to judge for yourself. A good test image would be a portrait taken outdoors with blue sky in the background.