Prefab—or prefabricated—homes can be an affordable and eco-friendly alternative to buying a new home built onsite. And sometimes, these modern houses can be super gorgeous.

Case in point: these modern modules by Seattle-based Node combine to build something like a custom home, with mix-and-match parts that offer both energy efficiency and seamless interaction with the surrounding environment.

”Not everyone wants, or can afford, a custom residence,” says co-founder and Seattle architect Matt Wittman. Wittman’s firm, Wittman Estes, built Node’s concepts and oversaw the first two home constructions.

Node, says Wittman, aims to “create thoughtful and environmentally sensitive dwellings that achieves our design aspirations and sustainable objectives while at the same time making design less expensive.”

Homes start around $90,000, which will buy a 264-square-foot home with a sleeping area, a kitchen, and a bathroom. The “full monty” module, a 500-square-foot home that includes a kitchen, a living room, a study, a bedroom, and a bathroom, runs around $150,000.

Other modules can be added on either at the beginning or as needs change, from a small “flex space” to various bedroom modules to a 110-square-foot “writer’s cabin.”

Energy and water modules can connect to solar power and store rainwater. Semi-outdoor modules include pavilions that convert to bonus rooms and covered, outdoor hallways to connect the buildings. A greenhouse module can be connected with the water module—and for someone who wants or needs to operate totally off-grid, compostable toilets are an option.

Modules are built with a “low-impact foundation system,” that Node says are sturdy, but often doesn’t require excavation. All homes come with low-flow water fixtures and are built “only with sustainable materials that can be, or have been, recycled, sustainably harvested wood, and non-toxic materials.”

According to Node, the homes could become remote getaways, ADUs, or even a rooftop addition.

Node homes are available now in Washington, Oregon, and California, with reservable wait list spots open to the rest of the United States.