Keiser Homes manufactures custom modular homes in Maine, for delivery there and in New Hampshire, Vermont, Massachusetts, Connecticut, and Rhode Island.

From their site:

Inside an 80,000 square foot facility, we use a system developed to control every step of the building process.

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Because Keiser Homes is a wholesaler that sells through builders, we cannot give out pricing. We can however, tell you that our pricing is comparable to stick built homes.

They offer a wide variety of models ranging from 840 - 3,120 sf with 1-4 bedrooms. (Follow the above link for a complete list.)

Also, check out:

• slideshow of their Castle Brook model
• pictures of a house setting
• list of builders