I think it is general practice, and everyone here will tell you, that you should avoid any sort of cap cost reduction, but that you should pay tax, title, reg and fees upfront. If you are a current BMW lessee, you do not have to put down a security deposit on your next lease. Either way, if you have a little extra money kicking around, consider the multiple security deposit option. One is mandatory unless waived by BMW (for existing lessees), but you can put down up to 9 extra. Each one you put down drops your money factor (lease rate), thus reducing your payment. They don't drop the payment as much as a cap reduction of equal value, but the security deposits are refundable at the end of the lease term.