I wrote a fictional piece called "One Per Customer," and when the main character gets upset, he likes to throw his heavy glass paperweight through the office wall. He's a cop, and his office looks like it's made of Swiss Cheese.), wardrobe.

Mental Attributes
Personality, how they relate to their relatives, their intelligence and schooling, fears, wants, goals, dreams, priorities, drives, skeletons in their closets.

Environment
Where they live (house, trailer, apartment, condo), it's condition (new, old, dirty), how it's decorated (salvation army, creative on a budget, antique, fashionable), their job (politician, crook - if there's a difference), manual laborer, computer work), sports, hobbies, friends, enemies, pets (I have a pet wind-up goldfish in a jar of water. Low maintenance and high neglect threshold.), relationships (single, married, divorced, widowed, dating, kids).

As I said earlier, it depends on your personality and your writing style. I often don't do much of a character development because I like to see how my characters grow and I like to be surprised by my characters and stories as I write them. Because of this I sometime have to go back and make changes in paragraphs, or chapters, but the surprises are worth it.

So experiment and find out what you feel comfortable with. You can change it whenever you like.

Above all, find a way to write that you enjoy. That's what it's all about.