In The stage of prequalifying, you can obtain and compare the information about your financial scenario. This is the best time to shop around.
You can start your application after deciding to refinance. Your application should updated with the information that proves your income, assets, etc.
After completing your application, it will be drafted. Initial loan package will include your intent to continue and loan estimation.
This will review your details and update all your information based on your agreement, also request you for any additional details or documents from you.
On this final process, mortgage loan is approved if your all conditions have been met. Consider to not have any previous conditions remaining.