Call an accountant or a tax attorney right away and talk to them about business use deduction of vehicles. There's really no difference whether you buy or lease in many cases. There are also big incentives to go with an SUV -- they've tapered off some since 2003 or so, but are still very good.
Either way, it pays to know the rules. Writing off a vehicle can be very suspect on a tax return, depending on your type of business, business use, etc. You're going to want to keep good records in case the auditor shows up.
I've found that tax advice from car salesmen is not always too sound.
Cheers, John