That depends is the answer but probably not the one you wanted. You need to determine your individual needs and requirements and then choose what best fits. It has been statistically shown that a security system does deter crime.
If you search the Internet for “off grid security system” you will find a number of videos that may have useful information.
One company that has a highly rated system is at this link. We have no affiliation and receive no compensation for adding this link. It is one of the options and there are others of course.