It depends on what you're looking for: are you trying to have a design prefabricated? Are you looking for a pre-designed off-site built house? Regardless of which it is, you need to involve any off-site company at the very beginning of the process. Here's an article I wrote on Linked In a while ago with some basic things to keep in mind, and I didn't even delve into whether the company is volumetric or flat panel!
BTW, I would highly recommend Bensonwood, they have been the gold standard for high end off-site for the longest.
https://www.linkedin.com/pulse/demystifying-off-site-process-architects-mary-holley/?trackingId=IORDYLLyTQ%2BEh964%2FEKU2Q%3D%3D
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Mary Holley AIA
studioma2
Arnold MD
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