Difference in appraisal value between regular & prefab?

[DG A.]

I have a question for you appraisers out there. I'm working on putting together a deal where I build a new single family home and sell it.

Right now, it seems very cost effective and profitable to do this using a pre-fabricated home... where the materials are cut in a factory, then shipped to the job site, and the home is stick-built on site.

Is there any difference in the appraised value of these pre-fabricated/pre-engineered homes?

If there is a difference, what % up or down is it from a traditionally built new home (generally)?

This would be a one-off spec build on a vacant lot between other existing homes in Richmond CA or Oakland CA. Not a tract development or anything like that.