The term, "Good Faith Estimate" contains the word "Estimate." Until you submit a complete file and lock your rate for a specific time, things can and do change. If you got the estimate from bank "A" on one day and bank "B" on another, you really can't make a fair comparison based on rate. Rates can change multiple times a day which really makes it tough.
I would focus on the expenses on your form, how much is each charging for Origination or the Brokers Fee? Issues like Title and Escrow are typically third party fees and shouldn't be too far off. Ultimately you have to choose the lender who you believe will be most competitive based on what you see when you get it.
You can ask both lenders to update their quote for the same day and decide, but again, until you lock nothing is set.
I'm sorry this is so complicated. I hope all turns out well for you.
The interest rate quoted on the estimate is good until there are any changes in the market - usually not until the next day, but I have seen rates move - both up and down - several times in a day.
Also - conventional loans, and government loans at some lenders, have risked based pricing. That means higher interest rates for lower credit scores. Since I am usally providing an estimate before I have pulled credit - there may be a need to factor in the risk pricing for a client with credit scores less than 740.
When getting estimates from several lenders to shop for the best rates and terms. Negotiate the bank fees first, Settle on the 2-3 lenders with the best fees, and most knowlegeble and professional service,then call to compare rates on the day you are ready to lock in. You should not need to wait for an underwritting review before locking a rate
GFE doens't have the rate LOCK feature. You have to LOCK it in writting for rate to stay effective (30/45/60 days). My experience is bank/lender will not allow you to LOCK until they have reviewed your loan application and received a few key information. Then they will allow you to lock the rate. GFE is mostly about fees/cost ...
No rate is guaranteed until you choose to lock it in for a fixed period of time. Typically on a pre-approval letter it should disclose if the interest is floating, additionally, there is probably a disclosure that should read "rates are subject to change daily"
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