Electrical? on 1996 BMW 740iL

We have replaced several batteries (in a short period of time). If we do not run the car EVERY day for at least 45 min to an hour, the next time you try to start the car it is dead (click click click). We have also replaced the starter, ignition and tumbler. Several import specialist have looked at this car and say there is nothing wrong with it. I feel something is draining the "juice" while it is sitting between driving it. I wonder if anyone else has experienced this problem with this model. We have spent about $1000.00 trying to what the problem is. HELP

Asked by for the 1996 BMW 740iL
Sounds like there is a constant drain on the battery like an open circuit.