The situation is as follows: - The client wanted to buy a security DVR along with some security cameras. - The client wanted the DVR to be compatible with Mac. - We did not have anything compatible with Mac at the time, so he settled for what we had. This was 8 months ago. - One of the brands we carry has now made an update to be compatible with Mac. - Our client wishes to make a change. - The client is a close friend. He will be a customer for life unless we really mess it up. Possible resolution: Do we just go ahead and exchange the machines, charging only the difference in price (negligible) and installation fees? We'd be giving him a new machine and receiving a somewhat outdated one, so it'd be a net loss for the time being, but it keeps the client happy and on our side. So it'd be a profit in the long run.