- Price: Cost of plans are based upon how many units( 4-plexes ) are to be built. The more units built, the cheaper the cost per unit will be charged. We have some developments with at least ten units(4-plexes). We will require an engineered plot plan with the layout of units on the property to determine the number of units to be charged for. Contact us at 1-225-664-1455 with Questions. * we also have 5,6, & 7plex townhomes.