Heat Pump Runs all the time

I'm in the process of buying a house. On the home inspection the inspector discovered that the upstairs heat pump would not shut off even with the thermostat set to off. It is a split all electric unit with the air handler in the attic. The house and units are approx 12 years old. The thermostat has to somewhat still work because it shuts the air handler off and on properly, and it still heats the upstairs except the outside fan never shuts off unless you flip the breaker. We are buying the home at such a low price the sellers are unable to do any repairs, so I'm just trying to get an idea of what I'm going to be facing once we move in. Thanks for any info!