I have what I like to call a, "double decker, double wide", a two story modular. (four boxs)
If the foundation was built right, and the house was set right, you should have no problems.
It seems here that you have a faulty foundation that was not built on solid ground or built to carry the weight of your home. As your homes weight settles, it is causing your home to move, and causing all the cracking.
If you bought this as a package, I would be looking at my lender to solve this problem.
They should make sure things are right before they close.