I recommend you simply Google "auto lease vs buy analysis."
There are a number of excellent articles that will summarize the issues for you.
Re: taxation, for most W-2 based earners, you CANNOT write off any value of the lease unless you are using the car for unreimbursed business use.
The point raised about the depreciation hit in the fists years of ownership is a valid point. I sell many late model Porsches for the simple reason that after 2-3 years, the price/value equation is much more attractive to many folks.
Good luck!
Hybrid Mode
