Well in theory you can put $0.00 down if your credit is good enough what i do recommend tough is put at least your inceptions
Tax
Tag
First Payment
Bank Fees
Either way they are going to take it and then just add it to your lease but i would not put much more out keep your money and play with it or invest it remember it is a lease not a purchase if it was the other way i would say put as much as you can.