Can i Check for the Player Character in a Local Script ???

Hi thank you i have a little problem in a script i add to some specific player if they are allowed to fly in their character and then i have a local flying script and i wanna check in that local script if the player is allowed to fly in their character here is the code flying local script:

local Player = game.Players.LocalPlayer
local Character = Player.Character or Player.CharacterAdded:Wait()
local checker=Character:FindFirstChild("builder")
UIS.InputBegan:Connect(function(Input)
	print("checking...")
	if checker then
		--fly code
	end

end)

and in the server script i have this

local builder=Instance.new("BoolValue")

builder.Name="builder"
for y,players in pairs(plrs) do
	local character=players.Character or players.CharacterAdded:Wait()

	local buildertrue=builder:Clone()
	buildertrue.Value=true
    buildertrue.Parent=character
end	

but for some reason the player can't fly although they have the "builder" in their character