Be sure to get full approval from at least 2 sources ahead of your contigency expiration day.

During my escrow processing, I got approval from 5 banks or mortgage brokers with itemized breakdowns on the closing cost to compare. I carried 2 of them all the way to the last minutes (3 days before close of escrow) to make sure i have a mortgage to complete the transaction. In current situation, envn you have a high credit rating, 20% down, and a good salary, you may be rejected at the last minutes or get a higher rate than they proposed.