Jenny has great control over her fixed expenses, but as for her variable expenses...not so much. Her family is consistently teetering between $1,000 a month and $2,400 a month in variable expenses, many of which can be resolved with some simple shopping tweaks (like leaving your credit card at home when you go to the grocery store). Luckily, they’ve invested a fair amount of their take-home pay, have a stellar 401(k) match, and are about to have dual incomes once Jenny is out of school.