To quickly summarise.
I ran into issues because I messed some high school algebra: households had too much money to start with, and were buying everything up. I needed to add functionality to view time series of data from within the model to pinpoint the problem. (The problem with models of this type is that they generate large numbers of time series, so viewing the model evolution is a challenge.)
Now that the model seems to be behaving as expected, I am now adding in private firms. These firms resemble agents as they are normally thought of; the earlier model “agents” were actually aggregates. (My framework is a mixture of aggregates and agents.)
The objective is to get a model of a private sector interacting with a Job Guarantee — similar to the Monetary Monopoly Model of MMT.