The bank may not lend on the POH, but can be value to POH in some cases. You need to know the rents. Specifically, the difference between the lot rent and the total rent (POH rent and lot rent). For example, I’m thinking of one specific rent controlled park where the lot rent including trash/sewer/fees is $432 and a 3BR/2BA 24x40 960sf home rents for $1,695. After subtracting the lot rent, the home brings $1,263/mo, $15,156/yr. The cost of maintaining that home is nowhere near that. Assume $200/mo or $2,400/yr for maintenance/repair. That leaves $12,756/yr net rent. Subtract the lot rent of $432/mo, $5,184/yr. That leaves $7,572/yr net profit from the home rental, which at a 6 CAP is $126,200/value for that one POH, on top of the value of the park/homesite.
These are higher rents than much of the US. In many areas of the country, the POH rents won’t be much higher than the cost of lot rent plus maintenance/repair. So, for most areas, what I’ve written won’t apply. But it’s worth mentioning. If evaluating a park in higher rent areas like the real-world example I’ve given, using the rule of thumb “Lot rent only” would undervalue the park.