? about new background laws

[86k10]

I don't know if this has been covered or not but my question is after the background check for private sales kick in how does this work?

If I make a sale to another person and we meet up at the FFL dealer, do I take his money and give the firearm to the FFL and walk away so he can enter it into his books then perform a 4473 background check on the buyer? Do I wait until the buyer passes the background check?

Am I correct that once the FFL books the firearm he must transfer it out even to the original owner?

Any insight would be appreciated.