Not getting a rate lock in writing. When a mortgage company tells you they have locked your rate, get a written statement which details the interest rate, the length of the rate lock, and details about the program. Using a dual agent i.e. an agent who represents the buyer and the seller on the same transaction. Buyers and sellers have opposing interests. A dual agent in most normal situations cannot be fair to both the buyer and seller.
Most dual agents represent the sellers more strongly than they do the buyer.
If you are a buyer, it is much better to have your own agent who will be on your side. The only time you should even consider a dual agent is when you get a price break from using a dual agent. Buying a house without a professional inspection. Taking the sellers word that they have made repairs. Unless you are buying a new house where you have warranties on most equipment, it is highly recommended that you get a property inspection, a roof inspection and a termite inspection.