General equilibrium with producers and brokers existence and regularity

In this paper we prove the existence of general equilibrium with transaction costs generalizing Hahn's (Review of Economic Studies, 1973, 40, 449-461) model by introducing producers and nonconvexities (in particular we allow for increasing returns in transaction sets). We also recover any exchange economy as a special case and this allows us to analyze the effects of small frictions on bid-ask prices, consumption vectors and utilities. We prove that, generically, the induced perturbations are of the same order as the frictions.