No system is going to stop a professional thief if he has time, knowledge and the will to break in. Spend 50K if you want and they will still get in the long run. Do not make yourself a target. Do not make it easy for them. Do make reasonable precautions. Past that you are mostly fooling yourself.
Buy good insurance if you are worried about your investment. If that does not make you feel safe, with your other efforts, then sell your guns and bank your money. I read today the the Bank of New York is charging some depositors 0.13% interest to hold their money. Stock market dropped 500 points and the banks are charging you interest to hold your money. Times are getting real nasty and may get worse soon. Load two and be ready, change is happening and I do not like it very much.