what I am getting Prefab Tiny House?

Pre set water pipes, wires, and lights , Socket ,switch（ hot and cold water pipes, sewage pipes）with US standards

ceiling, floor, bathroom, toilet, kitchen, cabinets, bed room

(excluding sofa, kitchenware, chairs，bed, AC and heating equipment)

need a foundation and how to install it?

Need foundation

Installation requires 3-4 or more people, preferably with two forklifts and cranes

I am wondering how these houses would hold up in winter months- we live in a snow belt region

This house has a certain degree of cold and snow resistance, Earthquakes of magnitude 8-9, typhoons of magnitude 8-9,

But to prevent heavy snow, I suggest adding a roof