i saw this on termpro and being that we dont have a sticky for something like this i think it would be good info
Please feel free to add more to this list!
• ALWAYS use common sense. Don't 'bump' where you live, esp. if you live in an apartment
• If at all possible, avoid putting any stickers on your car (be it performance or audio) they just scream "steal me! steal me!"
• If you go to car shows/soundoffs, I suggest removing your license plate temporarily. This will at least make it hard for people to remember your car is packing what gear(s)
• Consider getting dark limo tint and car cover. Remember - out of sight, out of mind.
• when you go to a mall or a store, turn down your system at least 2 miles BEFORE you get there. When a thief hears you bumpin down the road, he will follow you till you park and jack your equipment when you leave. Anybody who's desperate for money will do ANYTHING to steal something.
• Please Please Please install an alarm. I know about 30 people who pack thousands of dollars worth of competition-grade Audio Equipments in their SPL vehicles and they don't even have a $100 car alarm How stupid can you be..
• 'modify' your car alarm.. It might be an overkill, but I'll install 10 additional siren around the car - two inside the hood, two underneath beside the cat, two in the trunk, and four in the cabin. Thieves don't have enough time to cut all those wires while they're blaring 130bD.
• I betcha right now I can guess where you all have your alarm brains.. they're under the dash. right? that thing can be disabled in less than 5 seconds! Don't be a fool, move that brain somewhere hidden. Mine has mixed wire colors and false wires all around, Not even a professional installer can unload it.
• modify your Kickpanels to hide the hood release latch under the dash. Mine is covering the whole thing so you will have to reach inside the kicks to pop the hood. One time I took it in for an oil change it took the guy about 10 minutes to figure out where the hood release is This is extremely important so that the thief can't disconnect your +12 source and disable your alarm.
• I can't emphasize enough how extremely important security screws are. These are oddly-shaped head screws that you can get from any hardware store. Nearly ALL thieves carry a flat screwdriver and/or phillips screwdriver all the time. A hex or square head screw will definately slow them down. If your amp is bolted to the amp rack like this, there's NO WAY they can take your equipment.. but make sure your amp rack is bolted as well.
• Ask your insurance provider if they can cover your equipment.
• Be careful on who you show your system to... remember that every person is a possible thief. Even people who post here.
• Don't leave anything "interesting" inside your car (cellphone, jewelry, heck even a quarter) this will only attract passerbys that can possibly lead to theft.
• make sure all your fuses are good and have the right rating. Moreover, make sure your equipments are FUSED. In worst case scenario, after an equipment is stolen, wirings short out literally putting the car on fire.
The next time you roll down the parking lot, remember to keep them bass down cause having a system is like having ***--- you'll never know when you're gonna get jacked //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif
4 more info heres the original thread
please read its very helpfull knowledge