What are modular homes?

Modular homes are treated the same as stick built homes. They are just as strong and will appreciate in value. When dealing with financing they are treated as a construction loan that is transfered into a permanent mortgage (same as stick built homes). Modular homes are built in factories but still require a local builder to finish them. Make sure your modular factory and your local builder are both good. 

Mobile home trailers (like double and triple wides) are not considered modular homes. Some retailers will use that term since "mobile homes" have a bad reputation. 

Whatever you decide on just make sure it is placed on a permanent foundation (either slab or full basement). Mobile homes are built on steel frames. If someone tries to sell you a home on a steel frame according the to HUD code - they are trying to sell you a mobile home trailer. They will depreciate in value and are hard to finance.

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A modular home is a home that is constructed in a warehouse instead of built on the homesite. That is the only difference. 

The foundation is obviously done on the homesite, and it's prepared to the specifications of the modular home model that was pre-selected. 

When he modular home is ready, it's moved to the homesite and placed on the foundation, secured, an then the roofing and other finishing (which can have a variety of stages) is completed. 

The advantages are numerous. Your home is NEVER exposed to the elements (framing rained on, etc). It goes up in a day (just the home itself, you'll still need time for finishing, roofing and city inspections) and there is no time lost due to poor weather during construction. 

The disadvantage is because it has to be able to go down a highway, the various components have size restrictions and some design elements are limited, but these are rapidly expanding with new design techniques. 

They are made of the SAME materials as a site-built home. 
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Modular homes have come a long way. These are not to be confused with a "mobile" home. Mobile homes are shipped to the site as one piece (sometimes two or three in the case of a double or triple wide). Mobile homes depreciate in value and hard to finance these days. Very limited design (can we say rectangle?). 

Modular homes are generally treated just like normal "stick built" homes when it comes to obtaining financing from a bank. Modular homes even qualify for "construction loans" from lenders as well. 

A modular home is bulit in panels at the factory. These panels are trucked to a site where they are assembled. Sometimes they are referred to as "kit homes". There are tons of styles out there to fit every taste. 

If you want to build your own home but don't necessarily want to spend so much money, modular homes are a good way to go. There are lots of choices out there, just google it. Building costs are roughly half of that of a "stick built" (sticks, bricks and nails). You can find modular homes in the $75-$125 sq. ft range with assembly on-site. 

One of my clients is a log home builder. These log homes are "modular" but cost upwards of 500K each. They are "very nice" and you couldn't tell the difference between those homes and one built the good old fashioned way.