This paper presents the design methodology and control architecture of an aerial manipulator operating in indoor environments. The critical challenges of functioning effectively in such environments are (i) maximizing workspace in constrained spaces like narrow corridors or tight corners, and (ii) achieving stable flight when lifting payloads of unknown mass in the presence of uncertainties. While aerial manipulation has been researched to some extent, few efforts have been made to address both of these challenges simultaneously. Our proposed design is a small vehicle with heavy-lift capability. We show that with the proposed aerial manipulator design, a viable solution to the growing need for assistive indoor technology is possible through the use of aerial vehicles. The aerial manipulator platform proposed in this paper is unique in several aspects, capable of performing various tasks which before may not have been possible. Control law design, including an attitude and a rate command augmentation system, a feedforward torque compensation system, and an L1 adaptive augmentation law, are discussed in detail. To facilitate the design process, a simulation model is built to conduct control verification before implementation on the real vehicle. Simulation results are presented to verify the design.