Homepin, is 'for the life of the machine' defined in the contract? In IT there is a lot of equipment that comes with a 'limited lifetime warranty', where the lifetime is defined as only 3 years (for example). Your's sounds more like an unlimited lifetime, which would be a very good thing!
My contract makes is clear that it is for as long as the owner wishes to keep the machine going so that means basically it is open ended.
Sounds like you worked out a good deal!
