Before buying a timer make sure to look at the voltage of the pump. I have bought 2 Intermatic T 103 timers because that's what is hooked up to my Polaris. I thought I wired the first timer up wrong, but come to find out the pump for the filter is 220 not 115 so I burnt out 2 clocks. Now I have to buy a third timer this time a T104, 208-277 volts so I won"t burn out the clock. Easy to wire up and put the tabs to set on and off for the filter pump. The original timer on my pool pump lasted over 20 years, a good investment. You can get them for 60-75 dollars. Even with an electrician your looking at $150 tops.
Rick