p reconstruction Pricing in Key Biscayne! Brand New Construction! Immaculate design and attention to detail. Sigma Builder Best Builder in K.B. more than 8 homes finished each one delivered in less than 6 months from dirt to master piece product. arch itectural dream home, imported kitchen and flooring! Beautiful large impact window with impeccable views. Attention to detail w/high end finishes throughout. Open layout with a lot of natural light, volume ceilings and spacious bedrooms.