I'm no security expert, but I have read a fair amount about this topic, thought a lot about it, and have talked with several police officers about it (I've worked in and around city halls all my adult life, so police are readily available). What I've put together, and practice, is this:
Above all else, make your house looked lived in while you're gone. Ideal is to have someone whom you trust live in your house while you're gone. This creates a "normal lifestyle" appearance. If you have gardener or housekeeping service, keep it going. Make everything look normal.
Second best is to have a neighbor check on the house once or twice a day. Have them bring in paper, mail, turn lights on and off, take care of pets, etc. It is better to have a neighbor take care of paper and mail than to cancel those services, because believe it or not, some mail/paper carriers are not to be trusted. Add to this approach a few programmable timers for lights, music, etc.
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