For first, you can't remove value with variable, only update the variable not the value in object,

Example:

-- Default value: 2
local myValue = workspace.myValue.Value -- A IntValue
myValue = myValue - 1
-- Object value: 2, Variable value: 1

Its simple to fix, only use .Value on remove example:

-- Default value: 2
local myValue = workspace.myValue
myValue.Value = myValue.Value - 1
-- Object value now: 1, Variable value: no variable of the value.

(for see more of the .Value see the answer of Incapaxian, you can understand more: Incapaxian Answer)

Fixed scripts:

On your client, only use game.Players.LocalPlayer, also for fire RemoteEvent you dont need to send player, the first argument of the RemoteEvent is the PLayer

local event = game.ReplicatedStorage.RemoteEvent -- Location of your event
local price = script.Parent.Parent.Price
local tools = game:GetService("ReplicatedStorage"):WaitForChild("Tools")
local tool = tools:FindFirstChild(script.Parent.Parent.ItemName.Value)
local player = game.Players.LocalPlayer

script.Parent.MouseButton1Click:Connect(function()
	event:FireServer(price.Value, tool.Name) -- Only send price with value, not object and toolName here.
end)

In your event script put this:

local event = game.ReplicatedStorage:WaitForChild("RemoteEvent") -- Location of your event

event.OnServerEvent:Connect(function(plr,price,toolName) 
	local stats = plr:WaitForChild("leaderstats")
	local Point = stats:WaitForChild("Point")
	
	local tool = game:GetService("ReplicatedStorage"):WaitForChild("Tools"):FindFirstChild(toolName) -- Tool location

	print(Point.Value)
	if Point.Value >= price then
		Point.Value = Point.Value - price
	else
		print("You dont have money.")
	end
	print("Done!")
end)

Well this remote event is not protected so I would recommend you create the price inside the tools and check if the player has the money on the server.

For use protected RemoteEvents only put the Price(with IntValue named as Price) inside the tool and only send the name of tool to server

(Client)

local event = game.ReplicatedStorage.RemoteEvent -- Location of your event
local tools = game:GetService("ReplicatedStorage"):WaitForChild("Tools")
local tool = tools:FindFirstChild(script.Parent.Parent.ItemName.Value)
local player = game.Players.LocalPlayer

script.Parent.MouseButton1Click:Connect(function()
	event:FireServer(tool.Name) -- Only send toolName here.
end)

(Server)

local event = game.ReplicatedStorage:WaitForChild("RemoteEvent") -- Location of your event

event.OnServerEvent:Connect(function(plr,toolName) 
	local stats = plr:WaitForChild("leaderstats")
	local Point = stats:WaitForChild("Point")
	
	local tool = game:GetService("ReplicatedStorage"):WaitForChild("Tools"):FindFirstChild(toolName) -- Tool location
	local price = tool:FindFirstChild("Price")	
	if price then
		print(Point.Value)
		if Point.Value >= price.Value then
			Point.Value = Point.Value - price
		else
			print("You dont have money.")
		end
		print("Done!")
	else
		print("Price not found")
	end
end)

Hope it helped :D

Wiki pages

RemoteEvents/Functions

Errors? tell-me on comments.