What to ask when buying a used car?

I'm thinking of buying a used Honda of Craigslist. It seems like a good car for 3k with 150k miles but i want to make sure nothing's wrong with the car so what should i look for and what questions should i ask?

You ask to see maintenance records. You take a competent mechanic to look over the car. You let him tell you what he thinks. The owner will say anything to get you to buy the car. Beware if it has an obvious problem and the owner tells you it's a minor fix. If it was minor they would fix it before they sell it to get a better price. If you decide to buy it carefully check the title. The VIN should match and the owner on the title should be the person who signed it. Make sure if it showed a lien that the lienholder has signed off on it. No clear title… No sale. No exceptions. Don't be the fool that buys a car without a clear title.

You need to have the vehicle inspected by a shop that knows Honda. If seller will not, then do not buy the car.
List the model and trim level for more specifics to look out for.
Sure you can ask questions to get more info, and ask to see any service records, but the seller can lie, give a basic type answer… Car runs, seems OK to me, but is sold as is, or the seller may have no idea there's some problem.
Pull are full report from instaVIN.
And keep in mind a used car with that type of miles is going to need various repairs and maintenance.

Why are you selling?
How long have you had it?
What repairs does it need?
What repairs have you done to it?

The first thing to ask is "Why am I thinking I'm going to get a great deal on Craigslist, the most fraud-ridden advertising medium in the semi-civilized world?"