Lenders are required to issue a Good Faith Estimate (GFE) within 3 days of when the have the borrowerâ€™s name, monthly Income, Social Security number (to obtain a credit report,) property address, estimate value of the property, loan amount, and anything else the lender deems necessary per their written policy. Most compliance departments will not allow their loan officers to issue GFEs unless they have all of these documents - and then they usually need to be checked over to make sure they are correct.
The reason for this is an actual GFE is not what the name implies; it is a commitment, and the lender will be required to pay for any inaccurate estimates - even if the estimated fees are NOT within their control. This includes fees that the SELLER will be paying. I spoke to a fellow lender the other day, and he neglected to put the City Transfer Tax a GFE that the seller was paying, and he had to pay it. This makes lenders very reluctant to issue GFEs until they have to. In your case, unless the offer is accepted thus meeting the "property address" requirement, you probably won't get one.
What you should get is what we used to call a GFE before the government changes the rules. These documents are call everything BUT a GFE, but almost always do a much better job of explaining what you can expect to pay, to whom it will be paid, and what the total payment will be. (The government required documents doesn't actually tell you any of these things in a manner that most people can understand; that's why it's being changed.) You should be able to get this "non-GFE" form at any point in the process, and get updated ones each you change something like price, who will be paying what, rates, etc.
However the most important thing you need to get is your loan officer to go over all the documents and explain everything in detail. This takes me a minimum of 10 minutes, to as much as 30 minutes for some borrowers just for the "non-GFE" alone. A typical real estate transaction is comprised of about 20 different transactions occurring simultaneously, so don't expect it to be easy to understand. Ask questions and make sure you understand everything. Once you get an accepted offer you should get an updated "non-GFE," and you will get the official GFE within the required 3 days along with a bunch of other forms. Again, feel free to go overt these with your loan officer and make sure they all make sense. Don't be afraid to ask questions; you should have plenty.