Thats how I started out too, and my credit score rocketed. I was young and had no expenses so $40 in gas a month and food which was paid in full each month was perfect. Another thing is: if you are looking for more mortgage info try putting a post up in the mortgage section of this site. (The CC section has more visitors and posters then other sections but you should be able to get some good advice down the road when you need it)
CHASE FREEDOM | AMEX BCE | | BOFA REWARDS | CITI TYP | Quicksilver | DISCOVER IT | Sallie Mae | CHASE CSP
--------$32,000-------------$30,000-----------$30,000-----------$30,000-----$13,000---------$18,200----------$15,000---------$6,500----
FICO - TU: 780 EX: 784 EQ: 781