Taxes, including federal, state and local. If your combined income bumps you into a higher tax bracket, these higher rates should be assigned to the second income.
Social Security contributions
Withholdings for redundant benefits (i.e. benefits paid for but which would
be received anyway through your spouse's work.)
Transportation/commuting cost (gas and appropriate amounts for insurance,
depreciation, repairs). The easiest method is to use this cost-per-mile
schedule: 34 for subcompact, 39 for compacts, 43 for midsize vehicles,
49 for large cars, 70 for luxury cars. 39 x 20 miles/day x 250 days = \$1950
Would you need this car if you quit work? If not, then tally the annual car
payments
Image expenses: How much more per year does it cost to drive the right car,
belong to the right clubs, be seen at the right functions?
Tools of the trade: Is a car phone an important tool for work? What about a
portable computer, specific software, modem, business books, home office
supplies, fax machine, subscriptions to trade magazines/business papers?
Clothing: yearly expenses for work-related clothing stuff you wouldn't buy
(or perhaps wouldn't even want) if there weren't for work.
Dry-cleaning costs for work clothes.
Grooming: haircuts, makeup, cosmetics -- whatever is over and above your
needs for home.
Daycare and babysitting (Note: Daycare kids get sick more often so add a
small percentage of doctor's bills).
Lunch: How much is spent eating out? (Note: A homemade lunch cost about
\$1.50 and there are ~250 working days each year).
Dinner: How often are you eating out because you lack the postwork energy to
cook? (Note: A homemade dinner costs about \$3 per person).
Guilt: anything purchased for the kids or spouse to compensate for time away
from them.
Pick-me-ups/decompression: could be anything from alcohol to double lattes -- those items purchased to help relieve job stress.
Unresearched expenditures: Lack of time means no comparison shopping for
everything from food to furniture, insurance to electronics. On all these
items, you're spending around 20 percent more than necessary.
Home maintenance: housecleaning to house painting. How much are you spending on jobs you would like to do yourself if you had the time?
