user2212: Recently I came across a situation: a payment was executed by a customer on a site but then the consumer changed his mind.
What levels of transaction revert of such activity can be done?
e.g. X invested a coin into a dubious looking site and now there is no response from the site or site is taken down and site owner disappeared. Now what next can be done?
Can a smart contract react to such situations where I put a timeline for response to revert payment back?

user2201: Your question as to what levels of transaction revert of such activity can be done is an a way the question: what provisions should be in a contract for this of business. Although there are plenty of ways to create an appropriate contract, it remains a contract between parties that are expected to handle in good faith. And that may not be necessarily the case with the example you mentioned.
That said: in the case of a ongoing investment on could envision a type of contract which remains active for the whole duration of the investment and which includes a provision for the investor to request a return of the funds, e.g. first into escrow in preparation of a timely return after an agreed period. Of course this assumes that there are funds there to be returned ...

user1130: There is no way to revert a payment. One of the core features of a blockchain is that it is immutable (unchangeable).
As for smart contracts, you could definitely write a script to hold the funds in escrow. This would allow the parties to verify that the goods were passed before the funds are handed over.
This still wouldn't be "revert"ing, but could protect the customer in a similar way.

2212: <p>Recently I came across a situation: a payment was executed by a customer on a site but then the consumer changed his mind.</p>
<p>What levels of transaction revert of such activity can be done?</p>
<p>e.g. X invested a coin into a dubious looking site and now there is no response from the site or site is taken down and site owner disappeared. Now what next can be done?</p>
<p>Can a smart contract react to such situations where I put a timeline for response to revert payment back?</p>
 2201: <p>Your question as to what levels of transaction revert of such activity can be done is an a way the question: what provisions should be in a contract for this of business. Although there are plenty of ways to create an appropriate contract, it remains a contract between parties that are expected to handle in good faith. And that may not be necessarily the case with the example you mentioned.
That said: in the case of a ongoing investment on could envision a type of contract which remains active for the whole duration of the investment and which includes a provision for the investor to request a return of the funds, e.g. first into escrow in preparation of a timely return after an agreed period. Of course this assumes that there are funds there to be returned ...</p>
 1130: <p>There is no way to revert a payment. One of the core features of a blockchain is that it is immutable (unchangeable).</p>
<p>As for smart contracts, you could definitely write a script to hold the funds in escrow. This would allow the parties to verify that the goods were passed before the funds are handed over.</p>
<p>This still wouldn't be &quot;revert&quot;ing, but could protect the customer in a similar way.</p>
