local coinCount = 0  --coins inserted

function tenTimer()  --starts 10 min timer and then turns rs on right side for 1 sec then turns rs off
  rs.setOutput("top", true)
  sleep(5)
  rs.setOutput("top", false)
  os.startTimer(600)
  rs.setOutput("right", true)
  sleep(1)
  rs.setOutput("right", false)
end

function twentyTimer()  --starts 20 min timer and then turns rs on right side for 1 sec then turns rs off
  rs.setOutput("top", true)
  sleep(5)
  rs.setOutput("top", false)
  os.startTimer(1200)
  rs.setOutput("right", true)
  sleep(1)
  rs.setOutput("right", false)
end

function thirtyTimer()  --starts 30 min timer and then turns rs on right side for 1 sec then turns rs off
  rs.setOutput("top", true)
  sleep(5)
  rs.setOutput("top", false)
  os.startTimer(1800)
  rs.setOutput("right", true)
  sleep(1)
  rs.setOutput("right", false)
end
local ten = 1
local twenty = 2
local thirty = 3

print("How Much Time Would You Like To Buy?")
print("1 Gold Coin = 10 Minutes.")
print("You May ONLY Buy Up To 30 Minutes.")
print("Enter Number Of Gold Coins:")
write("$")

goldCoins = read() -- i want it to ask the user to input gold coins, quanitity of 1-3

  while true do
      local event, p1 = os.pullEvent()
        if event == "redstone" then  --if redstone pulse
          coinCount = coinCount + 1  --then add 1 to coinCount
            if goldCoins == coinCount and coinCount == ten then  --if coinCount, coins they inserted, is equal to goldCoins, how many they said, then start 10 minute timer
			  tenTimer()
			elseif goldCoins == coinCount and coinCount == twenty then  --if coinCount, coins they inserted, is equal to goldCoins, how many they said, then start 20 minute timer, This is where my code seems to error "" bios:14: [string "startup"]:50: '=' expected ""
			  twentyTimer()
			elseif goldCoins == coinCount and coinCount == thirty then  --if coinCount, coins they inserted, is equal to goldCoins, how many they said, then start 30 minute timer
			  thirtyTimer()
			else  --if nothing is true then break
			  break
			end
        end
  end