Bad credit, I'm paying it off to get an apartment any advice? ?

Hi, I have terrible credit. I am paying it all off with the exceptions of my student loans so that I can get an apartment. Do you have any advice? I also have to write an appeal letter to the company that owns the apartment. What type of things should I put in there? Man I need this apartment bad. Its the only apartment in my childs school district and renting a house for 1300 a month is out of the question. Any advice would be greatly appreciated. I am also curious how bad are student loans looked upon?