Clark frequently fields one question from the public when he's on the road during his book tours: "When is it right for me to lease a vehicle?" With the leasing market up about 25 percent year over year, it's a great time to address this question again. There are two circumstances when doing a lease is acceptable: The first is if you like new wheels all the time and you only want to worry about gas, oil changes and routine maintenance on your vehicle. Then it's OK to lease a new car every two or three years, but no longer than that. The second instance is when luxury automakers offer factory-subsidized leases where they eat a lot of the cost. Luxury automakers hate to cheapen their brands with a bona fide sale, so often they offer such leases to help move extra product. But other than in these two circumstances, don't lease. And stay away from four or five year leases unless you want to face financial Armageddon, Clark says.

Meanwhile, the strong growth in leases means that in a few years there will be great deals on two and three year old cars when they enter the used auto market. Clark is a big fan of used cars, but be aware that you must always have them inspected by an independent mechanic before you buy. Finally, beware of one cousin of the long-term lease -- the balloon loan. This is the kind that starts with an extra cheap monthly payment, but at the end of five or six years you may owe the lender up to $10,000 or even $15,000. And by then, your vehicle's worth won't be able to keep up with that inflated balloon rate.

Clark made a prediction in January that ended up wrong. He said gas prices would be a lot lower by this summer. He says he really blew it on that one. However, he made another prediction several years ago that may just be turning out to be true. He predicted there would be increasing demand in the US for shared cars services. Two companies who are doing this are Zipcar and Flexcar. These are services where you can rent a car by the hour just to do your errands, and just return it to where it was parked when you're done. Gas and insurance are usually included. It's kind of like "public transit, private driving," and it's much cheaper than adding another car to the family fleet! It's expanding like wild fire to many American cities, and even to some suburban markets. Since cars are such a huge part of our daily budget, it can save you a lot of money. It's like owning 1 and 1/4 cars, instead of 2 cars, or a time share for a car. But everyone knows that's not a term Clark likes to use -- so he prefers to call it "shared ownership!"

An oldie and mostly baddie is back -- car leasing! Clark thought the practice had gone the way of the dinosaur since manufacturers, dealers and consumers all got burned by it. The question now is, "When does it make sense to lease a vehicle?" There are really two such situations. The first is when you're talking about luxury automobiles. Luxury brands don't want to give discounts and cheapen their image, so they do it in a hidden way by subsidizing the lease. BMW is a great example of this -- almost two-thirds of their vehicles are now leased. Jaguar and Audi are other luxury brands that are very into leasing. The other situation where leasing is OK is if you like new wheels all the time and you don't mind that depreciation is demolishing your wallet. Then leasing a new car every 24-36 months is understandable.

But be honest with yourself. Make sure your lease doesn't come with an exceedingly low mileage allowance and beware of excessive wear-and-tear assessments in the future. The average leased vehicle gets hit with wear-and-tear charges to the tune of just under $2,000. When you get a leased vehicle, you should take extensive photographs of the interior and exterior so there's no question when you return it in top shape. And if you do spill something in the car or tear the upholstery, fix it before returning the car. It will be one-fifth cheaper for you to pay to have it repaired. Finally, before you return the leased vehicle, make sure you've gotten a third party to do a thorough inspection of the car. This alone could save you up to $1,500 in unnecessary turn-in fees.

Clark hasn’t talked about leasing a car in a while, mostly because he doesn’t normally recommend it. But he has an offer he wants you to know about just this once. If you like new wheels every 24 months or the manufacturer is offering special subsidized financing, it’s ok to lease. And that subsidized lease from the manufacturer should last no longer than three years. You should not lease because you think you’ll get more car for less money. That’s just plain hooey. Also, if you’re in a lease now, you can refinance it if you have good credit. How does it work? Well, there is no requirement under law that you’ll be told the actual interest rate on your lease. You’re basically borrowing the car, so the terms are always skewed. If you refinance your lease, you will be paying less and can get out of the lease earlier! Get help doing this at lowermylease.com. Just remember that you never want to extend the length of the lease, regardless of whether you get a lower rate.

About a week ago, Clark talked with a listener who was interested in taking over someone’s car lease. Clark told the man that it’s illegal in many states and that a lot of the people involved are running scams. Apparently, there is more to the story. The automotive writer for the New York Times actually tracked this information down in an effort to “sublease” a vehicle himself. A number of Web sites even exist now to help you. So, how is it legal all of a sudden? There are a number of banks that are worried about repossessions, so they allow customers to sublet a vehicle if the new lessee qualifies under their credit standards. So, Clark’s former answer was incorrect, but he still says to be careful in this tricky kind of situation. So, why would you want to take over a lease? The person who wants out of the lease has to pay you money to take it over. And it may be worth it to you if you don’t want to be under the lease anymore. The problem is that many companies out there are targeting people with really poor credit, and those are people who should not be getting into a lease – ever. Clark doesn’t like anyone to lease, especially people with bad credit. Also, a balloon payment plan is the worst kind of lease you can do, so don’t take over a lease with a balloon payment. And remember that there is an illegal side to this, so be careful. And, if you can avoid it, don’t ever lease a car.