The antonyms of the words "cheap and dirty" would be "expensive and clean." The word "cheap" refers to something that has a low cost or poor quality, while "dirty" denotes something that is unclean or unsanitary. The opposite of cheap is expensive, which means something is costly or high-quality. On the other hand, the opposite of dirty is clean, which means something is spotless, hygienic, or free from dirt. When we hear the phrase "cheap and dirty," we usually think of something that lacks a certain degree of value or dignity. However, the antonyms, "expensive and clean," would suggest the opposite: something that is of high value or that can be trusted.