Use the fee rate priority that mempool is suggesting.

For beginners: https://mempool.space/
For advanced users: https://jochen-hoenicke.de/queue/#BTC,24h,weight

If you are the seller, make sure the transaction has at least one confirmation before accepting the payment. It will be better to prefer to wait for 3 to 6 confirmations if the amount is huge. Do not accept unconfirmed transaction.

Thanks a lot! What about buyer reassurance?
I mean something REALLY valuable. Not a coffee or gas tank!

Well, make sure that you're receiving what you paid for?

Take note that by default, you can't do cashback through bitcoin. If you want to potentially get a cashback if it's the case that you received a fake item or something, use escrow.

Buyer’s assurance is make sure you have confirmed the goods before initiating the transaction, once you broadcast the transaction it gets a block confirmation you definitely can’t get a reversal except if the seller reverse it by himself or on rare occasions a chain reorg drags it down to the mempool again where you can double spend.


Then wait for Atleast 3 confirmations and at most 6 confirmations because a transaction left on the pool still unconfirmed can easily be double spend to another address by the buyer using the RBF method. A case like this was suspected on this thread when a scammer/buyer double spend or replaced the same unconfirmed transaction to another of his own address

Bitcoin transactions are tricky business because once you hit send, that's it - no take backs! As the buyer, you've gotta be super careful to avoid losing your money.  Personally, I'd triple check that Im sending my coins to the right wallet address.  Can't get that money back if it goes to the wrong person! I'd also look into the seller see if other people have bought from them and confirm they're legit.  

Make sure you fully understand what youre buying - read the fine print so there's no surprises later with extra fees or policies.  Check that everything's legal where you live too, just in case you need to dispute something later on down the road.  For expensive  items, I might consider use an escrow service as an extra layer of protection.

basically, with Bitcoin you gotta look before you leap.  Verify everything cover your bases, and only send payments when you're 100% sure its all good.  It takes more work, but better be safe than sorry when that crypto's gone for good!

While paying for an expensive item or making a huge transaction, first of all,, try to use a a wallet that supports RBF, and it would be advised to use this feature to enhance the fee so that your transaction won't get stuck in the network. In the past few few days,, I have seen two cases where the transaction has been stuck for quite some time. So if you don't want that, then increase the priority of your transactions by increasing the transaction fee using RBF.

Second, I would advise you to check the receiving address properly. There is no doubt that you have copied it from the main source, but still, you have to check word for word as many scammers have found a way to trick you by creating wallets that has a same start and ending letters in them, and many scammers are using clipboard attacks, in which the address changes when you copy it and it goes into the the clipboard.

So if the transaction is very large, then do not just copy; instead, write it down manually. Check the network you have chosen to see if that's right or not.

both parties can give each other  a bitcoin address. this can then form a multisig. a 2-of-2 spend-able multisig

the buyer funds the multisig. like putting funds into a escrow/joint signing account
this ensures to the seller that the buyer has the funds and the funds are set aside locked into a contract he is now part of.

when the buyer is happy with the service and the seller is ready to be paid. they both sign the funds to go to the sellers single bitcoin address. both signing a tx giving relevant fee to ensure speedy confirmation..

its like trusting your wife by not trusting your wife. putting funds in a joint bank account needing your and her signature means she cant spend money on other things and you cant just take her money either. you both have to agree on who gets it and what for and both sign where the money goes

.. escrows are how house purchases are done... in bitcoin, its called multisig

This one is good!

Yeah I remember like 10 years back doing a P2P transaction. The guy wanted to wait for it to confirm. I used the recommended fee but I think in that 10 minute period something happened and fees went up momentarily.

I had to wait like 1.5 hours for it to confirm because the guy wouldn’t  part with his cash. It would of reached the point where one of us would have to just trust the guy that it would confirm.

But in a p2p meeting, don’t be cheap and use a high fee. You don’t want it to be an awkward transaction.

If you wont really be using some payment processors and really that tending to receive BTC on your own non-custodial wallet and if you do have someone to make some transaction, then just like on what other
posters been saying that if this one involves huge amount then having 1-2 network confirmation would really be that suggested or if you are really that paranoid with those double spend
then 6 confirmation above but i could say that 1 network confirmation would suffice. You could already assure that you could really be able to get those coins.

Never ever release or make deal or finalize something on a unconfirmed transaction yet it could really be having that possibility of double spend on which this something that
should really need to avoid or simply you would really be scammed on this case. Always have that network confirmation first before proceeding on releasing items or giving out some service.