It is a different policy, not a variation
Manufactured and mobile homes are written on their own forms by carriers who specialize in them. A standard homeowners policy is not simply more expensive for one, it is generally unavailable. Owners who bought through a general agent sometimes hold cover that was never right for the structure.
Settlement basis matters more here
Many manufactured home policies settle at actual cash value rather than replacement cost, which on an older unit can be a fraction of what replacing it costs. Replacement cost is available from some carriers and it is the single most consequential term on the policy.
Installation and tie-downs are rated
How the home is anchored, whether it sits on a permanent foundation, and its age all affect both price and whether a carrier will write it at all. These are physical facts about the unit rather than judgments, and they are worth knowing before shopping.