If you really, really wanted to, you could buy a tank. Unlike a space shuttle or something truly unobtainable, it does in fact have a price, if astronomical. But if you want people to think you have a tank, you're in luck if you have a couple hundred bucks laying around.
At full scale 1:1 ratios, these inflatable replicas of various tanks are both affordable and durable—up to military specifications. That's right, there is a military specification for inflatable tanks.