When a credit card offer says "0% Intro APR on Purchases for 18 Months. 11.99% APR after that" - does "after that" mean the 11.99% rate applies to purchases made during the intro period or only to purchases made after that first 18 months?
Check the fine print. Often 0% intro rates are much higher if you carry a balance past the intro period - they'll charge you back interest. Read the fine print very carefully.