Re: Quick question on ellipsis.
In the process of buying a house, you make an offer to the current owners.
They may or may not accept your offer. You don't make any payments until after you have bought the house -- and there is no house to buy if the current owners don't accept your offer.
You can't actually get a mortgage before you have identified the specific house, but you can be qualified by the lender to have the mortgage. In such a simple example, you don't need these differences.
If you made an offer without first getting qualified, and they accepted your offer, you may find the bank doesn't think you are good credit risks and not loan you the money. Now you have made a contract to buy a house that you cannot pay for.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.