If you plan to use original supplies (toner or ink), or remanufactured
supplies and want to print a lot of text, then you have to buy laser
printer. Their cost per page for text is up to few times lower than than for
an inkjet, text looks superior to any inkjet, have better longevity and
water resistance - which is important if you print documents. Printing is
REALLY faster. And toners usually last for few thousand pages, which makes
it more convenient than inkjet, where you will be forced to replace
cartridges every few hundred pages. The costs of color prints may be lower
if you count the fact that you don't have to use expansive photo paper to
achieve good looking prints, but is usually not as cheap as printing with
black cartridge. Unfortunately color laser printers are much more expansive
to acquire than inkjets.
Good inkjets offer best photo printing quality (especially multicolor, low
droplet ones), relatively low purchase cost, take less desk space than
lasers. You can easily find affordable inkjet for larger paper formats (A3,
A2). Unfortunately they are slow, paper trays are small, ink lasts for just
few hundred pages, and original ink is decisively overpriced, as well as
original photo paper. The cost factor changes dramatically if you want to
refill cartridges yourself with third party bulk ink. This way an inkjet
printer has the lowest running than lasers. But refilling is a dirty work.
BTW. If you print really a lot of text then the lowest cost per page belongs
to photocopy machines with printing function.