My one vendor keeps telling me that the copier is cheaper to run than my desktop printers but my other vendor says the opposite.  Who is right?

Both and neither.  Fact is, there is no absolute in this comparison or in any cost comparison for that matter.  Most copier and printer reps are speaking from a lack of knowledge or a wealth of misinformation.  The copier people will tell you that desktop printers average $0.05 to $0.06 an impression and they could be right.  Of course your printer could very easily be costing you $0.01 an impression too and you copier could be at over $0.10 an impression. It all depends on utilization and total cost.  The largest difference between the two is toner yield because it tells you the toner cost per impression.  Toner yield is based upon a rough figure for page coverage, which means how much of a page is covered by toner.  For example a 5% page coverage means that 5% of the page is covered with toner  Most printer manufacturers use a 5% page coverage model (which is to say that with copiers you do not have to worry about this because it has been built into your supplies cost per impression).  Copier people love to quote desktop printers with coverages between 30% and 40%.  The average is actually between 10% and 15%.  We get that figure from the copier world where all digital copiers run about 10% to 15% on coverage which is significantly above what analog copiers used to run.  The reason the coverage jumped up with digital copier is because most people use them as printers, hence the ability to correlate printer and copier toner coverage. 

 To illustrate this we will use two different scenarios.  The first will look at a properly utilized printer and an under utilized copier and the second will look at the reverse.  To keep all things equal we will use retail cost for all equipment, supplies and maintenance and look at leasing all equipment over 60 months.  We will also use remanufactured toner for the printer and an estimated yield based on 15% page coverage rather than the 5% that HP quotes.  For the copier we will use a Canon ImageRunner 5000 with the 2 tray finisher and network Multi PDL board (print board).  To keep things equal we will use the HP 9000mfp.  Both units copy and print at 50 impressions per minute.  The Canon has a maximum monthly rating for 200,000 pages per month and the HP 300,000 per month.

Scenario #1	Copier	Printer		Scenario #2	Copier	Printer
	Canon IR 5000	HP 9000MFP			Canon IR 5000	HP 9000MFP
Equipment Cost	$ 23,350.00	$19,396.00		Equipment Cost	$23,350.00	$19,396.00
Monthly Lease	$583.75	$484.90		Monthly Lease	$583.75	$484.90
Monthly Service Base		$54.17		Monthly Service Base		$54.17
Monthly Impressions	5,000	60,000		Monthly Impressions	60,000	5,000
Impression Cost*	$0.010	$0.017		Impression Cost*	$0.010	$0.017
Total Service & Supplies Cost	$50.00	$1,009.48		Total Service & Supplies Cost	$600.00	$84.12
Total Monthly Cost	$633.75	$1,494.38		Total Monthly Cost	$1,183.75	$569.02
Cost Per Impression	$0.127	$0.025		Cost Per Impression	$0.020	$0.114
* Impression cost for the HP includes the Maintenance Kit used every 350,000 impressions and a reman toner with an expected yield of 12,500 impressions				* Impression cost for the HP includes the Maintenance Kit used every 350,000 impressions and a reman toner with an expected yield of 12,500 impressions

In this example the Canon is cheaper to run the 60,000 impressions on, but if you were to change the yield up to the rated 30,000 impressions the opposite is true.