There isn't a foolproof method to completely prevent a seller from engaging in a bridge scam. However, besides following the previously mentioned tips to prevent scams, there are other measures you, as a seller, could take to reduce the risk, such as:
If you want to make a large sale of Sats, it's preferable to split it into several smaller sales, unless the buyer has a good history of transactions with you and consistently uses the same bank account.
Be cautious if a buying offer seems too good to be true; it might be a scam.
In fiat payment methods that allow adding comments to the transfer, you could ask the buyer to write a specific phrase you mention at that moment, like "I'm buying an orange." This way, if they were a scammer, they'd have to ask the victim to write that comment to send the fiat, which could raise suspicion as it's highly unlikely that they are buying an orange.
You can modify that phrase to a numerical code or another message you find appropriate to prevent a scam. Another method, though not highly recommended due to privacy concerns, is to request the phrase to be: "This payment is for a purchase of X Sats on @lnp2pbot for order ID: Y."
Some fiat payment methods don't allow adding comments but reveal both parties' phone numbers. In such cases, you could ask the buyer, before releasing the Sats, for an SMS from the number that sent the fiat, containing any of the aforementioned messages or similar messages. Another approach could be a call initiated by them or you, directly confirming no third-party involvement in the fiat transfer.
Another option, not highly recommended if you wish to respect the buyer's privacy, is to request a video call on Telegram where they show they possess the card from which they sent the money. However, they don't need to show their face for this purpose.
Remember, if you're uncomfortable with a transaction, you can engage in a cooperative cancellation with
/cancel and return the fiat to the same account from which it was sent. If the other party is unwilling to cooperate, you should open a dispute with
/dispute and wait for a solver to resolve the case.
The preventive measures mentioned here may not apply to all fiat money payment methods. If you're aware of other methods, please share them and contribute to preventing scams.