Most every mobile home park owner in the U.S. has a list of rules attached to their lease which is longer than the lease itself. While it's always a good idea to cover your bases and address every possible behavior concern, it's another to expect people to follow more rules than the local prison.
More importantly, what's in it for the park owner?
It's my theory that you should not expect to hold mobile home park residents to a higher standard than those of the folks who live in brick houses in the nearest subdivision. It would make sense that someone who lives in a mobile home is less likely to obey the rules than these stick built home occupants, so why are their park rules ten times longer?
Take a drive around the subdivisions nearest your park. What do you see? I'm betting you see the same things you do in your park. High grass, junk in the yards, non-running vehicles and the like. They are just better at hiding it because you can't see into their back yards as easily, and the non-running vehicle is up on blocks behind the house. Still, the general quality of violation looks a lot like your park.
My point is that humans, regardless of demographics, violate certain rules as a regular part of their existence. It may not be aesthetic, or morally right, but trying to fight it is like trying to stop the Mississippi River, basically impossible.
Does that mean that you should reduce the number of rules attached to your lease? No, you want to have every contingency covered. However, you may want to think again about what you enforce, and how hard you enforce it. For guidance on this concept, let's look at a typical city government and what it asks of its residents and how they force compliance.
- High grass: In most cities, having grass over a certain height, normally 8" is a violation of code. As a result, violators will generally get a warning and a deadline to comply and, if not completed, will get a fine and/or someone from the city will mow it and bill you for it. They don't threaten to evict you, and they don't set the rule at some ridiculously low level like 4".
- Non running vehicles: If you don't get rid of them, after receiving a warning, you will get a significant fine. If you don't pay the fine, you will get arrested. Perhaps we can substitute "arrested" for "evicted" in the park rules theology.
- Junk in yards: Again, if you don't clean out your yard, they will fine you and force you to pay. However, you have to have a lot of junk to trigger a code officer writing you up.
- Aesthetic issues: Painting your house for example. This is hardly even covered in most city ordinances, because they only deal with the absolute worst, most community damaging offenders. They don't get involved in the small stuff, and maybe you shouldn't either.
- Just about everything else: Loose dogs, loud music, etc. This is a police matter. It should be for your tenants too. You should not get involved in being the enforcer. That is what police are for.
I think that this is really about all you need to follow on rules enforcement. Some owners have built a career on rules. They spend every waking hour harassing tenants and sending threatening letters, but does it make them any money?
Some might argue that it does in the form of making the park more desirable looking for new tenants, or park buyers or lenders. I would agree, but you can always "doll up" the park right before putting it on the market or refinancing it. As for new tenants coming in, let's get serious, how many new homes are being sold and moved into parks in your area? That's what I thought.
As for resident retention, you are just as likely or more so to scare off existing tenants with a lot of rules and tough enforcement. If they wanted a beautiful, problem free environment, they shouldn't have moved into a mobile home park in the first place. Further, I have found such demanding tenants never stick anyway, since they are always unhappy and end up moving out no matter what you do.
In conclusion, try taking a more mellow, practical view to rules and their enforcement. Your life will improve, and so will your tenants. You can devote those "rule enforcer" hours to more productive uses, like making money.