I agree that one may have free time to sell. This free time is leisure time. For many, the house of leisure they have is not much so that their leisure time being scarce, the tendency would be to put a high price on it. Still, there are very many households where work is performed at more than one job where finding people who work two part-time jobs is not very difficult. And there are some people who work as many as three part-time jobs to make ends meet for themselves and for those for whom they provide the necessities of life. The numbers of jobs a person works is a function of many variables. What do you think some of these variables are and how do you think they interact with a person's number of jobs held? Are there macroeconomic variables that come into play?