These situations seldom cost much money to solve. We have an attorney call the city attorney and work it out over the phone for around $500 to $1,000. If they can’t work it out, we push it back on to the seller to fix before we close (although we’ve still not had a case where they have to litigate). We would never buy a park without this question decided before we actually close – we have no interest in walking into litigation. But the fact is that city hall caves in really quickly these days because there is so much case law on the topic, and the park owner has won every time in every state Supreme Court to date.
If it’s not something you want to get involved in, then don’t do it. But most of our best deals are in markets in which the city has high housing prices and hates the ideas of more trailer park residents. In poor markets with nothing going on, city hall would never fight you because they’re desperate for anything that brings in $20. But in the type of markets where SF median is $200,000 ands apartment rents are $1,400 per month, you better expect to get some type of fight.