How to sell my house & land, if the house is personal property (paying a mortgage) and the land is paid off?

I want to sell my home. My land has been paid off for decades, passed down from my great grandfather to my grandparents, to my parents, then to me. I bought a new manufactured home in '98 and had it put on the land. The tongue & axles were removed immediately, when the home was placed on the concrete runners.

The Appraisal District told me that no one can get a mortgage on my home unless it's showing as "real property", and they told me to call the Manufactured Housing Division of the Texas Housing Authority. I called them, and they confirmed that and said that they can't change it to "real property" without written consent from my mortgage company. So I called the mortgage company, and they said that they will NOT give the consent because I'm still paying for it.

So, it seems that I can't sell my house until it's paid off, but I can't pay it off until I sell it…

Do I have to sell the land & house separately? Can someone get a mortgage on my place despite what I'm being told? Will my chances of selling it be diminished due to this complication? Is it even worth putting it on the market? Am I doomed to live in this 3 bedroom house until I pay it off? My wife and I have 5 children, and we desperately need a 4 bedroom!

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