Did you have the opportunity to review a sample of the lease before signing the actual lease as required by New York State Law? (Here is a link to the statute: http://codes.lp.findlaw.com/nycode/PEP/9-A)
If not, then you nay have an argument about a right to cancel, but otherwise the lease will control your rights.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.
Bring lease to a lawyer to review with respect to termination clause immediately.
If this answer is helpful, then please mark the helpful button. If this is the best answer, then please indicate it. Thanks. For further information you should see an attorney and discuss the matter completely. If you are in the New York City area, then you can reach me during normal business hours at 718 329 9500 or www.mynewyorkcitylawyer.com.
For many types of high pressure purchases in NY there is a 3 day statutory right to rescind, but not with auto leases. I would suggest you contact the dealership and/or leasing company and explain that the disposition fee was not brought to your attention and that you want it waived. You may file a complaint with the NYS Attorney General's Office if you reasonably believe this was a deceptive trade practice, although that claim may fail if the disclaimer language in the "no money down" advertising materials mentioned the disposition fee. If it did not, and it was not otherwise brought to your attention, you can use that as leverage with the dealership/leasing company to get the disposition fee waived, at least partially.