We study optimal portfolio decisions for a retail investor that faces proportional costs which are floored and capped at some minimal and maximal cost levels, respectively, in a classical Black-Scholes market. We provide a construction of optimal trading strategies and characterize the value...

In dynamic portfolio choice problems, stochastic state variables such as stochastic volatility lead to adjustments of the optimal stock demand referred to as hedge terms or Merton-Breeden terms. By deriving an explicit solution in a multi-agent framework with a stochastic opportunity set, we...