Quantum Instruments Calcu-Flash II not turning on.

I recently bought a Quantum Instruments Calcu-Flash II light meter from eBay. When it arrived I tried it out, but (according to the manual) the display indicated that it needed new batteries. So I went and bought replacement batteries (4x LR44 batteries) and changed the old batteries. However now when I try to turn it on, the display won't light up at all, not even with the old batteries (which it did just prior to changing the batteries). I've made sure that the battteries are inserted the right way round, and even tried moving them about a bit.

Has anyone ever experienced something similar? It seems odd to me that it would die so suddenly. Obviously I'd return it to the seller right away, but I fear that shipping might cost more than what I paid for it originally...

Ancient electronics trick is take an eraser (pencil type rubber) or better yet the old hard white rubber typerwriter eraser to the contacts and make sure they are clean of oxidation. If a threaded cap make sure the threads are clean also.