A casita is a detached, freestanding structure — typically a guest house with its own entrance, bedroom, bathroom, and sometimes a kitchen. It operates as an independent living space separate from the main home. A room addition is built onto the existing house, expanding its footprint with new bedrooms, living areas, or primary suites. Both require City of Las Vegas permits and HOA approval in most Centennial Hills communities. Kingdom & Co. designs and builds both throughout the northwest valley.