Hi!
My first post on PPrune

. Been watching a long time, but never had anything useful to post!! But, being a long time sim pilot I might be able to help here.
Cheeselover, As someone said earlier, it would actually be cheaper for you to get another printer than to buy, even second hand charts.
The latest European charts are available online at the relevant AIS site and plenty of links have been posted for you to find them.
With US charts, I have recently found a site
http://www.fltplan.com Once you log in, it allows you to enter a departure and destination airport, then shows you any presaved routes that are in it's database but also provides a list of DP's/STARS/IAP's and aiport charts that you can select. They are in GIF format so will load in no time and can be saved for later printing. The last time I checked, any charts I pulled were up to date and correspond to the latest AIRAC cycles.
I know it's a pain to print, but, it is definitly cheaper and speaking for myself, I'm not going to fly into every airport that has charts, so I only print out the charts that I use most frequently. Saves a bit more time and ink

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I think they also have Low and High alt charts aswell that can be printed.
Anyway, hope this helps.
Cheers!
PB