Research: Printing costs

I started to wonder the best way of printing my t-shirt designs, however i remembered that i had recently bought a new printer at home, which would be more than capiable of printing my needs. However looing at this from a business perspective, i eneded to find out costs of printing, so that i could assemble to price into the budget and cost analysis. I looked online and found the best quotes for cartridges that i would be needing, would be £17. As you can see from the images. This cartrige will easily allow me to print 20 designs at a very good quality ratio. This brings the costs of printing to 85pence per unit.