Dave has just made it through his last semester of school. Classes were challenging, so he had to cut back on the number of hours at his part-time job. As a result, he was not able to keep up with his bills for the last two months prior to graduation. To help ease the situation, Dave applied for a new credit card and transferred the balance of his existing two cards, avoiding the necessity to make a payment for either of those cards that month. The following month, Dave was short on grocery and gas money, but Dave's new card was at its limit so he ended up using both of the old cards he had initially planned to cancel. Dave also incurred a number of expenses while getting ready to move following graduation. Additionally, Dave needed a whole new professional wardrobe and took advantage of a department store's discount offer by opening an account. Dave are now ready to start his first post-graduation job in a new town. Dave is horrified when his application to rent an apartment in an ideal location was turned down do to his credit report.

What things did Dave do in the last three months that hurt his credit score?