loking for the best way to save currency values?

I'm making a dollar but im trying to find a way to where hackers cannot manipulate the dollar amount aka getting more cash than theyre supposed to get. so im looking for the safest most reliable method:

methods ive tried: 1.clicking a dollar in workspace then it adds to leaderstats then saving the leaderstats data every minute or so but i was thinking that was very exploitable? not sure

2.running this script i got from another member here but it doesnt detect new dollars that are added after the game is already running

	for _, detectors in pairs(workspace:GetDescendants()) do
	    if tostring(detectors) == "dollar" then
	        	detectors.ClickDetector.MouseClick:Connect(function(playerWhoClicked)
	          	 print("OwO UwU")
			detectors:destroy()
	        end)
	 
	    end
	end