What is your price range?

How far are you willing to commute?

Is it important to be close to a school, a place of worship, etc.?

What type of lot or yard do you want or need?

Do you need a garage? (How large? Attached or unattached?)

How much maintaining or updating are you willing to do?

How many bedrooms/bathrooms do you need?

What other requirements do you have? (# of levels, size, storage, etc.)