Competitive two-sided markets with complements

We consider a two-sided buyers & sellers' market with indiviseble goods. Agents may trade many units of any of the items available. Previous research, documenting the case ofunit-flow trades, showed that the existence of substitutability or complementarity colligations between goods. These relations are in ingrained in the agents' utility representation. Straight forward extension to the general setting cares for the instance of substitutes. We investigate here the less propitious case of complements. We formulate a set of conditions on utilities and on goods that warrents the existence of a competitive equilibrium for this market.