Bank transfers are 100% safe.I mean I don’t really want to get into a massive debate/argument over it, but I’m not talking about reversal of a payment, more if the ‘buyer’ states fraud has occurred. Basically if the buyer contacts his/her bank and says fraud has been committed, they will investigate as you say, and IF the money can be clawed back (for example they can prove fraud) - it will be. Only way it won’t be is if the account it emptied. In this instance I doubt it would be.
Again in instances like this the person receiving the money MAY have their account frozen (probably temporarily) until the investigation is complete. They’d likely have to submit all kinds of evidence - chat logs etc. It’s not a nice process.
Like I say I used to work in the fraud dept for a high street bank. Also go read the MSE forums about bank accounts being closed for no reasons because someone linked to fraudulent activity has sent them money.
Ultimately, you do you. Me personally for such a high amount I’d steer well clear.
BUT don’t tell people bank transfers are 100% safe - they aren’t. Don’t get me wrong if you’ve done nothing wrong then you SHOULD be ok, but only after the actions above have been carried out.
P.s you can trust me on that!

Banks offer more support to customers who make online banking slip ups
Major banks and building societies have signed up to the voluntary code, which will give customers greater protection if their money does go astray.

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