Send the machine back, stop all payments and tell them you are going to sue them for damages for misrepresentation. The upgrade you were promised was not the upgrade they gave you and at no time were you expecting to pay more than you were before. If they sue you then you would have a misrepresentation defence and you could try to say that you weren't given the chance to read the contract nor was it explained properly. Not great but I think you would get the sympathy of a court. Why would you want a franking machine at a cost which is greater than buying stamps? However as I say I think you have to fight fire with fire in the meantime. I hope that helps. Please leave a positive response so that I am credited for my time.