We went through this recently. We used the cover letter. Also applied well out of the price range we wanted to, while applying for everything that was suitable and we didn't stop looking while the applications were being processed. We stopped looking the first time and the house fell through so wasted time. By going to so many inspections and talking to the agents they came to know us as locals too which helps in the area we are. As a lot of applicants are young (fresh out of high school)and from out of town