have a good thing going
Have matters arranged to one's benefit or profit. For example, Joe's got a good thing going with this new franchise. It also may be put as make a good thing of, meaning "make something work to one's benefit," as in If we work hard we can make a good thing of this job. The first term dates from the second half of the 1900s, the second from the early 1800s. Also see have going for one.