the only way that any deal here is made is like this.
Step 1.- Seller anounces he is willing to sell ( usually gives price and preffered payment Method )
Step 2.- Buyer gets in touch and offers the cash offer ( usually not many buy more than 1 BTC)
Step 3.- Seller deposits the BTC in the Adress of one of the Escrows ( the Buyer Usually chooses it)
Step 4.- Escrow gets in touch with the Buyer to let him know that the BTC is in his adress.
Step 5.- Buyer Makes the deposit, Transfer or the desired payment method.
Step 6.- Buyer Shows proof of deposit or transfer or any other usually with a picture or video
Step 7.- Escrow Releases the BTC Sending them to the Buyer´s Adress- AFTER SELLER CONFIRMS AND SIGHTS CLEARED FUNDS ON BANK ACCOUNT
_Bussines Concluded_
That's the safer way. Never rely on screen shots or pictures alone. Ascertain, check and double check that funds are 100% cleared and credited to the account without any form of holds or restrictions. Then and only then should escrow release the coins.