I bought a safe from Home depot about 8 years ago. It can be opened by keypad combo or using a key and cost around $100. I pulled the drawers beneath the closet and through bolted the safe. I used quarter twenty SS bolts with large flat washers and lock nuts. Could someone get it out? Probably but it will take time, tools and make a fair amount of noise to do so all the while not knowing what if anything they will get.
Our 10 year old 24' Class C does not exactly reek of wealth so hopefully most bad guys would look for a more lucrative target. The typical thief hitting an RV is a snatch and grab opportunist looking for a quick and easy score.
We use the safe to store spare keys, cash, prescription meds, electronics etc.. In states where possession of a weapon can be problematic {I can legally CCW in 37 states} my unloaded pistol legally resides there but remains quickly accessible.
Most law enforcement will tell you that anywhere you hide valuables pro's can usually find them. The safe/install has worked well for us and if they want whatever happens to be in ours they will have to work for it. Some insurance companies will even give you a discount if you document a proper installation.
Bolt it down...
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