The sentence that is correctly punctuated is: I haven't found a new job, and I don't plan to look for one until I have to. The first sentence is the correct answer. What is wrong in the second sentence is the use of hyphens. It is supposed to be used in the compound word "day-to-day". And in the last sentence, it is supposed to be a semicolon after the word worse, because the sentence is a compound sentence.
