Ask HN: As a customer, how to stop non-criminal misconduct with small damages?

In our society, we have 2 systems for dealing with misconduct: enormously expensive lawyers and courts, and police (which often feed into the former). The former is effective if the money amounts in the dispute are large enough to justify paying for lawyers and filing fees, and everyone involved has the money to do so or high quality representation is available on contingency. The latter flatly refuses to deal with non criminal matters. But, not all reasonable (meaning that someone has done business in a dishonest way or has made a mistake and then refuses to make it right) claims fall into these categories.

Examples, that I have personally experienced in the last year, include:

- buy a used car from a private party who modifies the car between the mechanic inspection and delivery of the car such that it's degraded. This cost me $800 in parts to fix, as they swapped a part for a part from a different brand of car, thus making it unsafe via incompatibility

- a store sells sealed food that upon opening is damaged and inedible, refuses return and compensation for my time going back, and credit card company has blanket policy of no charge backs on food

- store says that they have an item that I need in a time sensitive manner, then doesn't have it over a weekend when all stores are closed. Root causes is inventory software not reflecting reality. Refuses to make it right. Making it right would be sending an employee to the next city over to fetch the item, or compensating me for costs in doing so. They said that they'd sell x on y date then failed to do so. I'd have gotten it earlier from other places before the weekend had they not given me false information. I understand that such mistakes happen, but not making it right after making a mistake is unacceptable

- private seller lies about an appliance and disguises the appliance to look like one type when it's another, then refuses to reverse transaction or compensate for lost time

On some of these things, some prevention seems theoretically possible, but that isn't a viable solution because the level of time and effort that's needed to do that in all cases is unrealistic. Furthermore, many of these (such as the appliance, car, and food item) are outright scams. Placing the blame and responsibility to fix it on victims rather than perpetrators is illegitimate.

What can I do when someone successfully pulls such a scam on me? There's a limited amount of this shit that I can tolerate before losing my sanity, and I'm very close to this point. We're supposed to have rules, but it seems impossible to enforce these rules so we might as well live in a free for all, but that's unacceptable to me. I demand accountability.