OP,
Sounds to me like you need a safe..But, before buying do some research, there are some wondeful videos on youtube put up by some lock and safe people that show how good/bad some safes can be. Most safe manfacturers today, have a cheaper Chinese made line they sell, try to avoid these, as they usually offer little protection.One example of that was on youtube, where, at one lock and safe company, they took a safe that many of us have probably seen, and may even own, it was a green safe, with a "Winchester" logo in the door.They locked it up, and using nothing but common pry bars, timed themselves, and pried the door open in 6 minutes.. The lesson here, is not how thick the composite door was, but how thick the plate in the front of the door was, in many cases this plate is less than a 1/8" thick.. Good quality safes by Amsec, Liberty, that are made in the U.S.A. are a good place to start, if you have a place where you live that sells safes, go talk to them, ask questions, if they show you a safe with a composite door, ask how thick the plate is in the front of the door, ask how thick the safes body is, do they offer moving for you after the sale?
Other things to consider, if you're planning on going away for a couple of days, do you have any tools laying around that could be used to attack a safe? Tools like right angle grinders, die grinders, electric chipping hammers, drills, pry bars,sawzalls, you might want to consider locking them up in the safe if you're going away for a few days.. No sense in making it any easier for them...
Any safe can be broken into if one is given enough time and has a few tools, Do some rescearch, talk to some people in the business, I'm sure there's something in your price range.. kinda goes with the old addage "buy once cry once" a good safe won't be cheap, but it's an investment that pays for itself with security it offers..
I myself bought the store safe from a local dept store that was going out of business, the safe I bought is perfect for handguns, has a 2hr fire rating @1850 degrees, it weighs 620lbs..The safe itself has a thin sheet metal outer shell the walls are made from some concrete like material that is 2 1/2" thick all the way around with a inner steel liner. One would have to cut a large hole in the outer liner, chip away the concrete like material and chip enough away to get the grinder in to cut open the inner liner.. not impossible, but,that's going to take some time, time most theives aren't going to spend on it.. at 620 lbs they're not walking off with it either..best of all, I bought this for $315,and paid a couple guys $50 to move it for me..