Nothing better then being in a transaction and the Buyers change their loan from Conventional to FHA without telling the Selling agent and then...ordering the appraisal. Buyers, if you are in a deal and you want to switch from Conventional to any other terms, YOU HAVE TO HAVE THIS AGREED TO BY ALL PARTIES. If your agent has not sent you and "Amend to Extend" to request changing terms with the Listing party, you are in breach and you might lose the deal! If you aren't aware of why this would terminate your contract, you are with the wrong agent for more than 1 reason at this point.
Do not change loan terms mid deal without an Amend signed BY ALL PARTIES!