Today on “Post Reports,” personal finance columnist Michelle Singletary offers up some of her time-tested, conventional financial wisdom.At every age and stage of life, we’re faced with making tough financial decisions. Am I ready to buy a house? Should I start saving for retirement? And what the heck is FICA? For nearly 30 years, Michelle has answered these questions for Washington Post readers. Now, she has compiled her most frequently asked questions in a new project, Michelle Singletary’s money milestones for every age.