Is my realtor right? Mobile(ish) home financing question

[Jason Hill]

I will be brief. I have a mobile home built 1973 (before the big HUD changes) that has what can only be described as a house built around it. It has a brick "skirting", a 2x4 exterior wall (that wraps around the metal siding), and a rafter roof slapped on top. However, my realtor says because it's still on a metal frame and has the doors/windows/ceilings of a mobile home it will be classified as such and traditional financing won't touch it. I know that a mobile home that has not been placed on a foundation will not be considered but I thought that was because it's still technically movable. This is very much NOT movable. You would destroy the home trying to move it.

As an aside this home is on 3 acres of land that will be included in the purchase.  The county classifies it as a traditional home, not a mobile home.