WTF? Yes, go ahead and advocate responsible techniques. But if you're the type of meddling busybody that harasses others just for working on their own homes, don't be surprised when nobody listens to you.
Led contamination risk is definitely more serious than HOA-hellhole
> if they don’t have a license or permit, how can you verify they are following best practice?
What exactly do you think licenses/permits guarantee? At best, an inspector knows the least responsible crews and checks in on them more often. That's about it.
The only way you can actually verify someone is following best practices is to know what those practices are and observe their behavior. By expressing a belief that permitted professionals somehow automatically conform and DIYers automatically do not, one indicates that one has no idea what best practices actually are but yet feels qualified to judge anyway.
Licenses confirm that the person doing the work is trained in the best practices + safety for the work that they are doing. Permits ensure that they have filed a plan with the city/state that matches safety regulations, and that this plan is available for the public to review and comment on. It doesn't guarantee automatic conformity, but it shows that their plans have been confirmed _and_ provides an avenue to verify that they are conforming to those plans.
I can't confirm everything that a doctor does either, but I'd still much rather see a licensed one than an unlicensed one.
Your neighbors' decisions around lead management and mitigation directly impact you and you are within your rights to insist that they follow proper safety procedures. To cast that as "meddling" or "harassment" is odious.
You do, in fact, "have standing" to not have your neighbors poison you. This is a good thing. It should be celebrated.
Legally, it's generally commercial activity (eg contractors) that is regulated. Thus, after you've talked to your neighbor about best practices for mitigating lead dust, you've effectively exhausted your options. After that point, not "letting" them DIY will basically consist of harassment.
As to your postscript--yes, clueless or careless DIYers probably need the hammer swung at them, and hard, when they do something to create negative externalities. You have the right to not be poisoned by your neighbors. Even if they make you sue them to enforce that right, that still isn't "harassment", and it is genuinely and deeply gross to characterize it as such.
I got rid of the PS because it was needlessly obtuse. But trying to restate it nicer - coming at someone DIYing with the attitude that they should be hiring "professionals" instead, as opposed to offering constructive criticism and perhaps even help, is a guaranteed recipe for a failed interaction.
And unless you've got actual demonstrable harm from your neighbor's activities - more than a vague worry about the possibility of lead dust being carried by the wind - filing a baseless lawsuit is indeed best characterized as harassment. At a certain point, there is an threshold of blame that is impossible to adjudicate. Slightly elevated environmental lead is squarely in that territory (it could have also come from a piston plane flying overhead), which is why the real fix is to systematically eliminate the use of lead to begin with.