How to stop grey market

1. Make sure that official service contractors only service items distributed through the local channel, i.e. don't service items bought in New York in the UK.

2. Make sure that a reasonably high proportion of your merchandise need servicing before the guarantee runs out. This can be done with providing a standard guarantee period that's longer than normal, say 2 years, and building the stuff so that a significant number would need servicing before 24 months, like having somewhat inconsequential bits falling off - people would want to have them serviced but if not, the items would still function, after a fashion.

3. Lay back and observe the gradual death of the grey market as consumers learn to treasure official warranty service 

How can the grey industry fight back? Source items so cheaply that the buyer could add on a 3-year warranty and still pay 30% less, which, given the level of greed in the pricing policies of certain official local distributors, is actually possible.