What rights does Owen have against Sparky for breach of contract and partial or full return of the money paid to Sparky?

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Sparky, an unlicensed electrical contractor, placed an ad in the local newspaper that read:

No Job Too Small, No Job Too Big!
Electrical Outlets Replaced-$15 Each
Call Sparky at (213) 555-1234

Owen, a residential homeowner, saw the ad and called Sparky. Owen told Sparky, "I saw your ad and am hiring you to replace a total of ten electrical outlets in my home." Owen and Sparky made arrangements to meet at Owen's house the next day. When Sparky arrived, Owen explained to Sparky that Owen wanted to change the outlets in two rooms that were recently repainted and Owen thought that the outlets would look nicer if the current ivory colored outlets were replaced with white colored outlets.

Sparky told Owen that he would do the job right now for $200-$20 per outlet. Owen said that he thought they had an agreement for $150-$15 per outlet as the ad said. Sparky told Owen the price was higher because the job was a small job. Owen told Sparky, "Go ahead and do it, I don't have much choice, however, I heard that outlets made by ABC were the best so I expect you to install that brand." Sparky went to his truck to gather the necessary supplies for Owen's job. Sparky then realized that he had used the last of the ABC brand outlets on a previous job and all he had left were XYZ brand outlets. Sparky grabbed ten white XYZ outlets and promptly changed the ten outlets in Owen's home without telling Owen that he was using XYZ brand outlets. Owen reluctantly paid Sparky $200. Owen was satisfied with Sparky's work but felt that he had an agreement with Sparky for $150 instead of the $200.

After leaving Owen's residence, Sparky went to Big Box, the local home improvement store, to replenish some electrical supplies for his next job, later that afternoon. Homer, a sales associate in the electrical department explained to Sparky an electrical problem that he was having at home. Sparky told Homer that because of the way Homer had always taken care of Sparky with finding material at Big Box, he would fix Homer's electrical problem for free. Sparky told Homer that the only time available would be 6:00 pm that evening. Homer agreed. Homer told Sparky that he would need to leave work early, resulting in two hours of lost pay, but he would be there by 6:00 pm. At Sparky's next job, Sparky ran into unexpected difficulties and was not able to go to Homer's home that night. Because of Sparky's heavy work schedule, Sparky told Homer that he would not be able to fix Homer's problem.

Owen subsequently discovered that Sparky used XYZ brand outlets instead of ABC brand outlets.

1. What rights does Owen have against Sparky for breach of contract and partial or full return of the money paid to Sparky? Discuss.

2. Did Sparky have an enforceable obligation to Homer? Discuss.