The one-claim warranty

With your new phone, the store offers a 12-month protection plan for $120. The plan pays for one repair only: the first fault in the year. Any later repair you pay for yourself. Each month, independently, the phone develops a fault with probability 3%, every repair costs $300, and a repaired phone can fault again in a later month. Compared with not buying the plan, what is your expected gain in dollars from buying it? A negative answer means the plan loses you money on average.