  We study a single risky financial asset model subject to price impact and
transaction cost over an finite time horizon. An investor needs to execute a
long position in the asset affecting the price of the asset and possibly
incurring in fixed transaction cost. The objective is to maximize the
discounted revenue obtained by this transaction. This problem is formulated as
an impulse control problem and we characterize the value function using the
viscosity solutions framework. We establish an associated optimal stopping
problem that provides bounds and in some cases the solution of the value
function.
