To use Bit2Factor proceed as follow:
1) Go to
https://bit2factor.com/ and click on "Generate Intermediate Code". Create a passphrase and click on "Generate Intermediate Code"
2) Send me the Intermediate Code generated at step (1)
3) I will generate BTC Address, Confirmation Code and Private Key and send to you the BTC Address and the Confirmation Code
4) Click on "Verify Confirmation Code", insert the passphrase and the Confirmation Code I sent you and click "Verify Confirmation Code"
5) If the escrow told you "OK" then I will send the bitcoins to the BTC Address I sent you at step (4)
6) You send me the PayPal funds.
7) I send you the Private Key
With the private Key you will click on "Decrypt Private Key" and enter the passphrase you enter at step (1) and the Encrypted Private Key I just sent you.
Click Decrypt Private Key.
You will receive the PRIVATE KEY (WIF) that you can import in your bitcoin wallet and have the XXX bitcoins I just sent you.
This gives you the guarantee of the transaction without using a person in the middle.
Sorry to steal the reply from TheKoziTwo.
That describes the process to use the BIP38 compliant escrow.
This is the description of the BIP38 feature: basically the sender (FIAT) retain the passphrase to have the guarantee in the transaction.
https://github.com/bitcoin/bips/blob/master/bip-0038.mediawiki