This paper presents a heterogeneous agent model of a sequential monetary production economy. A deterministic dynamic flow model is employed. The model is characterized by three classes of agents: a single homogeneous representative consumer, heterogeneous firms and a banking sector. There are three asset classes (or debts): a single homogeneous physical good, money and debt securities. The homogeneous commodity is produced by firms and, if saved, increases their capital stock. Firms issue debts to finance growth. Firms are homogeneous as regarding production technology but are heterogeneous relative to expected in°ation. Consumers provide labor force and make the decision of consumption and saving of their income. They own all the equities of firms and banks. The banking sector collects consumer savings and provides credit supply to firms. The main result of the model is that real economic variables are strongly affected by the level of credit supply in relation to the level of savings.