Average $90-$150 per square foot.
Modular Homeowners estimates that the average cost per square foot of a completed home to be built – not including the cost of land (including taxes or fees), the setup of utilities, or exterior touches (driveways, landscaping, and porches) – is $110.  The general Ballpark price for a modular home is about $58-$70 per square foot for our models with our standard, high quality specifications. Larger colonial homes tend to be on the lower end of this range, with ranch and cape styles being towards the higher end.  If you're wondering about modular home prices in New York, MH Imperial Homes states a price of $65 to 75 per square foot depending on options for a square-box house, but for a multi-roof house the price jumps to $75 to 85 per square foot. (MH Imperial Homes operates in upstate New York).  A “modular home price per square foot” is always misleading in part because the cost to build a home varies considerably depending on the design. For example, one-story homes are usually more expensive per square foot than two-story homes, if you keep everything else the same. You can add $10 to $100 per square foot to a home by upgrading from the fewest and least expensive features to a large number of expensive ones. For example, stained cedar siding costs much more than vinyl siding. To provide a rough estimate, the cost of modular homes in NJ is about $55 / square foot for the modular home, including the set, and about $45 / square foot for the additional finishing work, for a total of $100 / square foot.  1 An upscale 3,200-square-foot modular home delivered in eight pieces in Maryland had a base price of $300,000 but the extras, including a basement, septic fields, porches, a driveway, permits and other charges, bumped the total to about $560,000. 1 Prices start around $50,000-$60,000 for an 800-900-square-foot home (1 or 2 bedrooms, 1 bath) but can go as high as $500,000-$1 million for large, customized, high-quality homes. 2  And that's without the land, foundation or other site work. That is probably not the answer you are looking for but it is the most accurate. You should expect to pay about $90-$150 per square foot for a finished standard modular home. That means you can find quality modular homes for between $100,000 and $300,000. You may come across price quotes for $40-$80 per square foot. Those price quotes are typically not for a finished home. Some homebuyers spend over $100,000 to finish their modular home. You may also come across modular home prices for $150-$200 per square foot. 1 A slab foundation for an average 1,600- to 1,800-square-foot family home might cost about $7,000-$16,000 or more, while a slab foundation for a 3,000- to 4,500-square-foot home might cost $13,000-$40,000 or more. 
http://www.moneycrashers.com/building-prefab-home-types-cost/ http://www.avalonbuildingsystems.com/pricing-guidleines.html http://www.greenhomegnome.com/modular-home-prices/ http://www.the-homestore.com/handouts/modular-home-price/ http://www.rebuildnewjersey.com/the-cost-of-modular-homes-in-nj/ http://home.costhelper.com/modular-home.html http://www.modulartoday.com/modularhomeprices.html http://home.costhelper.com/house-foundation.html
average square foot cost of modular home