WHY BUY PRINTER CARTRIDGES BY THE BUNDLE /VALUE PACK?
You do save by bulk buying, but only if you have use of all the colours.
When you buy cartridges over the internet, an option you will often find is "B,C,M,Y Bundle" (usually for compatible/remanufactureds) , or "value Pack" (usually for genuines) as an option to purchasing a particular colour.
Should you take advantage of these options?
The answer most times is yes you should. If you look at the individual prices of each of the black, cyan, magenta, and yellow cartridges, you will find that if you buy all four individually, their collective cost will be often significantly higher than the bundle offer. Also if you choose to buy each one individually as you require it, you will most likely be paying for the shipping cost, often anywhere between $5 to $10, and sometimes $15+ charged by the suppliers whose cartridge price is unbelievably low. If the price of your cartridge is say $22 then this is a heavy impost.
But if you take advantage of the bundle/valuepack offer, and suppose you don't as have much requirement for colours as you do for the monocolour (black), you can end up with extra colours, not being used.
The solution for this is to order a bundle/value pack, and also order an additional black, or cyan etc, if that colour of cartridge is what you use more. You will pay more for the additional cartridge because singularly it doesn't attract the bulk buying discount, BUT you do save on additional courier costs, as most retailers will charge only the one courier fee, no matter haw many cartridges you order at the one time.