So here's a reality check Claudio. The printer you are thinking about buying will likely need a new belt and it might shred within a matter of weeks or could go for a year or two depending on when it was last changed, if ever. You have no guarantee even if you are handy that you'll be able to change the belt out and get it working. If it's a Z3200 and not a Z3200ps model, there will be even less support for it, than a newer model Z3200ps (both of which have reached end of life-meaning no HP support). You will have to get carts that are at least 1/2 full to be able to have the printer fully reset itself. There should be new printheads to give it a fighting chance. There's a steep learning curve to pull the best quality out of these printers, and people spend years, if not a decade mastering these machines making their art.
Many think, "oh boy a practically free printer" and don't fully count the cost before diving in with both feet. Been there, done that many times, but in the end, when you add it up, (like you seem to be doing), it begins to take a toll. So you could just pass on it and wait for one that is actually working, that has a known history, continuous use and has the ability to get into the error and warning logs, not to mention take it for a spin before buying. You jumping in there hoping for the best, won't make it so if it's got issues, and with these printers, even new ones have issues.
Some free sage advice for you. Let it go. Move on. Wait for the right printer to come to you.
FWIW/YMMV
Mark