How to allow player to buy a gun?

Hello.

Problem:

• You used LocalPlayer in a ServerScript. This will not work as LocalPlayer only works on LocalScripts.

Solution:

• Use the player argument of ClickDetector.MouseClick instead of LocalPlayer.

Recommendations:

• Use Clone() with an uppercase "C" as clone() is deprecated. It is never a good idea to use deprecated functions.

• You do not have to use WaitForChild() on the player's backpack as it will be loaded in.

• Use GetService() when indexing services as it checks if the service is existent. If it isn't it creates the service. GetService() is also useful if someone renamed the services. GetService() is the only way to create services.

• You do not need the else for the if statement on line 02.

Fixed Script:

script.Parent.ClickDetector.MouseClick:Connect(function(Player)
	if Player.LeaderBoard.Money.Value >= 500 then
		Player.LeaderBoard.Money.Value = Player.LeaderBoard.Money.Value - 500
		game:GetService("ReplicatedStorage").M18:Clone().Parent = Player.Backpack 
	end     
end)

Also, put local before declaring a variable unless you're using a global variable. Local variables are faster and more efficient than global ones though.