Stirling, is this is a more-or-less off-the shelf product, possibly with some incidental customization, installation, and/or training; or is it custom software or a product with a LOT of very customer-specific customization?

I've worked with many companies of all different sizes and serving many different markets...both domestically and abroad. I have never seen a request for 24 months of "warranty". However, maybe it is the definition of "warranty" that is part of the disconnect. Can you spell out their definition?

I agree with your initial comment that it needs to be built into the price. Nobody in their right mind would expect any definition of warranty for 24 months without paying for it. So, what's wrong with building 24 months of maintenance fees into the intial purchase price? It seems to me that becomes a great negotiating point. You can reduce the price if they are willing to back down on the warranty period. And, if you clearly define what is included and what isn't, what's wrong with locking them into 24 months of maintenance? I think it goes back to the definition.