Final closing disclosure. The last document you will receive from the bank just prior to closing. The clear to close needs to be issued for you to get this. This is not a naca process though it is a mortgage lending industry process. You are fine. You did the right thing.
For all intents and purposes yes. You have 3.125% plus buy down. Your rate cannot go up.
The reason your rate isn’t shown with the buy down applied is because this is a standard template form and the money listed as down payment/closing costs and seller assistance would normally go to those things. As a naca member it doesn’t; it gets automatically applied to the purchase of points (buy down), which, under normal circumstances is an additional fee and separate transaction. You will get documentation later on in the process that shows the points you purchased as well as the final rate after the points.
Everyone has a payment shock. It is a requirement. It is the difference between your maximum monthly payment (usually 31% of your gross monthly income) and your current rent. There is a minimum of $200 though if the difference is small.