The short answer is that a rezoning mid-hold does both things at once, and which one dominates depends on timing relative to your capital event.
A few definitions first. "Going-in basis" means what you paid for the whole property. "Net operating income" (NOI) is the cash the park produces after operating expenses. "Cap rate" is the ratio buyers use to value income properties: value equals NOI divided by cap rate. When a county rezones a parcel to commercial-adjacent, it does not automatically change the park's NOI, but a buyer may argue the land itself commands a separate valuation, which lifts the blended price. That is the upside the broker is describing.
The complications you named are real and they compound each other. A higher assessed value before refinancing can raise your property tax bill immediately, which reduces NOI before you capture any sale premium. A condemnation offer (where a government body proposes to buy the parcel compulsorily) gives you less control over timing and price than a voluntary sale. And a title review triggered by new interest in the parcel can surface easements or encumbrances that were always there but never mattered when the acres sat idle.
I have not modeled this specific scenario, and I would be cautious about anyone who presents a confident close-above-basis outcome as typical. The variables, your loan covenants, the specific commercial use permitted, the easement language, local condemnation law, are all deal-specific. A real estate attorney and your lender's asset management team are the right people to walk through this before the rezoning creates a forced conversation.
What I would ask you: do you already have legal counsel engaged on the park, or is this a hypothetical you are stress-testing before a future acquisition?
