Separating Schedule Cs?

--My wife has a 40/hr office job, plus does independent consulting out of the house in Education.
--I am self-employed, with my own office, plus I work out of the house as a writer.

Thanks to great answers on this board, I've about got a handle on how to do my taxes. But wanted to get some verification on my approach, with one follow-up question:

Based on the above, we will both file separate Schedule Cs this year (because we have separate business types), with separate deduction lists for travel and business expenses. We both have an office room in our house, with separate desks, and therefore claim dual home offices, which we separate on floor space (it is a 20x20 room, so we will both claim 10x10 for each) plus I claim my regular downtown office for myself.

My last question: We both share a car for business. What about when inputing items like auto insurance? Do we put 50% of insurance cost on hers, and 50% on mine? Or do we just put 100% on one or the other?

Thanks again!

My tax program seems to separate out a portion as business vs. personal, so it just asks me to put in the total insurance amount, repair amount, etc. So when I'm talking about 50/50 separation, I'm just talking about inputing half of insurance under her Sch C and half under mine.

I would split the deductions 50% on each Schedule C.. but for the car, make sure you don't use them for personal use, as well, because then you will have to decifer what amount needs to be broken out in the % for personal use, which is not a deduction on your Schedule C. Did you keep a mileage log? Claiming miles for each business would be an easier method to go by, but you would have had to have kept a log for all of 2007.
Additionally, if you are paying a home mortgage, the interest and property taxes are already on your itemized schedule A, so you cannot double take the deduction for the home office square footage on your Schedule C. Best of Luck.

50% on each. Instead of actual car expenses most people just use the standard mileage method of 48.5 cents per mile.

there's a question whether the same vehicle is used for more than one vehicle--yours is!
makes a difference in business use of vehicle. . . .
yes, you each take the business percentage you use, based on mileage
however, unless you have another vehicle for personal use, it's not going to be 50% each
IRS wants total miles driven, commuting miles, specific business use miles, leaving your personal miles out of this

do you both only use the car for business. If yes then I'd go with 50/50. If you also use it for personal reasons then you have figure out how much and factor that in as well.