This may seem inappropriate but I would hold off and buy a car from an enthusiast on the board - like the Pittsburg guy. When you don't have money and you sink it in to a car - if it blows up on you - you are in real trouble - especially since it will be your only vehicle.
Just a word of caution - that it is a risk and unless you have an additional 2 to 3K in the bank for just in case stuff - it might be prudent to get a hold of SVX gratification impulses till you are more settled.But hey - its free advice - which means nothing.