Fortunately Mike is an EXPERT on this so we should get a pretty good response

Hey, hey, HEY! Don't go calling me an expert. I have my pride, you know.
Anywho, there's not as much mystery about leases as some people (present company excluded, of course) seem to think. It's nothing more than another way to finance a car. I've traded out of every lease I've had, except for one. Well, make that two ... I sold one leased car car outright 3 months after I got it. But no one ever blinked an eye at the dealer end.
A leased car has a payoff amount at any given time, just like a financed car. You simply have to get enough for the car to take care of the payoff amount, or make up the difference. If you're like me, you never got enough trade-in value for your financed cars to handle the payoff either, so you're usually no more upside-down in a lease than in a purchase.
The IS350 I sold after only 90 days cost me a little over $3,000 "penalty", but I considered myself lucky to get out that light. Most of my other lease trades netted me about what the payoff amount was, so I've rarely had to pony up any meaningful money.
Just look on your monthly statement and get your payoff amount. Then check kbb.com or edmunds or whatever, and see what your car is worth as a trade. Subtract the difference if any and that's where you stand. Dealers have no problem paying off your lease after you buy from them, as it's no different to them than paying off a bank or other financing institution.