The main problem which can arise with this type of printer is that the PRINT HEAD COULD DRY OUT and you will get faded print outs or BLANK pages - if its not used on a frequent basis, no matter how much ink is left in the cartridges!
Turning ON the printer at least once a fortnight, - will reduce the risk of this happening. Use PLAIN copying paper to print off one page from any document that includes a graphic/picture. Save the expensive edible paper for the image transfers to your cakes!
Replacement Print Head for a Canon printer on www.anycake.com costs £57.00 where as each ink cartridge is £9.50
If ordering the printer by phone from this website sales staff ask if you will be using the printer on a regular basis, or not - hence the good advice on maintainance.
Today I posted a reply to CC on a thread called "edible images" started by di_stump with reference to this topic, which may be of interest to you.
Unpack the printer and make a start! I learnt alot from my own mistakes!!! Its a great bonus to have such a printer- once you get going you will be delighted with your purchase! Good luck!
Hope this helps.