There are, of course, far more than four questions to ponder before buying a car, but for now, this is an excellent start. The goal here is to help you center your mind, funnel your energy, and most importantly, keep you from making any expensive mistakes.
1. Which of the following are most important to me: fuel economy, space, creature comforts, color, safety, reliability, looks...? Some of the above? All of the above? Take a moment to list your priorities.
2. What is my budget? Do I have a monthly car payment range or a total out of pocket over time vision? What can I afford?
3. How patient am I when something goes wrong? Is it OK as long as my repair costs are covered by warranty? Or do I want to avoid any visits to the shop altogether beyond regular maintenance?
4. How much time am I willing to put into this? Do I want to enlist an outside service to streamline this large purchase? In other words, make sure, if at all possible (many exceptions of course if a car is no longer in working condition due to damage or mechanical reasons or both), that you have carved out a decent window of time (and this varies greatly from person to person) to make a thoughtful decision.
The more time you take to mentally prepare before diving into the ordeal of making a large purchase like this, the less likely you are to be swayed by the opinions of all the individuals that love to help influence your decision. Friends and family will often offer sound and welcomed advice, but those who are employed by a car dealership have varied agendas including the need to make an income. The strength of your convictions will go a long way towards keeping you on the path that will lead you to the right car buying decision for you and/or your family.