This is where you buy or sell weapons, armor, and of course, any vehicles that you will be using within the game. Unlike property that increases in price depending on the amount you purchase, the amount you pay for the weapons, armor, and vehicles stays the same for one shotgun or a hundred shotguns.

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You'll be able to see, at a glance, how much attack or defense points that any one of these three items will give you. This will aid you in your purchasing decisions. When you look at the inventory list, you will quickly see at a glance that the more expensive ones don't necessarily have the highest attack or defense - so be smart about your purchasing decisions.
Each of your Mafia members may fight with one weapon, one piece of armor, and vehicle. However, if you're not going to fight within the game, then you do not need to outfit every member with all this equipment because it gets expensive. I would hold off equipping your Mafia until you have the few million dollars coming in every hour. Instead, increase your property to get that good passive income hourly.