Self-Help Income. In which of the following situations would the taxpayer realize taxable income? a. A mechanic performs work on his own automobile. The mechanic would have charged a customer $400 for doing the same work. b. A mechanic repairs his neighbors personal automobile. In exchange, the neighbor, an accountant, agrees to prepare the mechanics tax return. The services performed are each worth $200. c. A mechanic repairs his daughters automobile without any charge