We found appropriate boudaries were most appropriately delineated with cattleprods, tethers, and other restraints, combined with not letting the little beasties out of the back yard (and removing the invisible fence shock collars) until high school.
More seriously, we allowed different behavior in different places in the house. For exxample, they might be able to bounce on the family room furniture, but not the living room. Or they could leave more toys out in their rooms or in the family rooms, than the general living space. They certainly were not allowed to damage something for no reason - tho if they wanted to take things apart or smash them, we would look for appropriate things on garbage day.
The kids were able to go pretty wild outside. But even in our yard we didn’t allow them to just shriek endlessly. Seeing as it would drive us crazy, we imagined it would do the same for our neighbors. And the toddlers might skinny dip in the backyard blow-up pool, but not at a public pool or beach.
We have some nice things in our house, and tho we certainly did a lot of childproofing, we did not let the kids dictate every aspect of our household for a decade or so. And we thought it important to teach the kids to respect property - ours, theirs, and other peoples’.
There is a big difference between making a mess, and damaging something. As far as making a mess is concerned - such as pulling the pans out from under the cabinets, or taking books off of shelves - our rule of thumb was if it kept them busy longer than it would take to clean up afterwards, it was okay.
In public, our thoughts were generally that they should not act in a way that imapirs anyone else’s reasonable enjoyment, or endangers anyone else or their property. I guess many folks might consider us overly strict, but our kids were the quiet/polite kids on the train or in restaurants. If we felt it would be too much effort to have the kids act as we wished, we would not take them. I can recal more than one instance when we left a store or mall because a kid was throwing a fit.
We tended to not go to childrens’ museums, as we felt those were often places where kids were allowed to misbehave - and we didn’t want the tension of having to decide whether to let our kids go along with that, or to teach them differently, etc. Plus, they are generally louder and more crowded than we like. I don’t know what exactly was involved, but “crash the lawnmowers” does not sound like something I would be thrilled with my kids doing, and I would probably tell them not to.
One thing we had essentially no tolerance for was “mean” behavior by our kids. And we taught them that they did not have to tolerate it from others.
The comment regarding “saying yes” is a good one. At one point I realized I was saying “no” a lot of the time, just because I considered it easier than deciding whether “yes” was appropriate.
Another thing I remember was it seemed I would often hear the kids arguing upstairs, while I was downstairs reading or something. For a while I would just yell, “What’s going on?”, “Cut that out!”, etc. Then one day it dawned on me that it was far better for me to haul my lazy ass off of the chair, put down my book, and walk upstairs to where the kids were, and check out the situation using a normal tone of voice.
Just a few disjointed thoughts.