I spoke to USDA - the home does have to be NEW, on land that you own or are purchasing, and the home must be purchased from an accredited dealer that can offer USDA financing. The home also has to be detitled and placed on a permanent foundation.
They are emailed me a list of accepted dealers that you can purchase from if you are interested in it.
A Group Real Estate
Feel free to contact me with further questions or if you would like some resources to help you unterstand the lending aspect better on MFG homes..