Leasing a car can seem like a great deal, especially when you see enticing ads for $199/month leases on brand new cars.

But leasing is not as simple as it seems. You may find that what you actually end up paying is much higher than advertised, and it's crucial to understand the factors involved. From inventory availability to money factors, here are five key things to know before you sign on the dotted line.

Advertising Versus Actual Inventory

National advertising campaigns often highlight incredibly low monthly payments for leased vehicles, but this doesn't always match reality. The deal you see on TV for a car like the Honda Civic or BMW 3-Series might not be available at your local dealership. These promotions are typically based on a specific model in a specific location that may not be available when you visit. Dealers don't always guarantee the advertised price, and they may direct you to a different model with extra features, which can raise the monthly cost.

Be prepared to either take a different model or face a price increase for the car you wanted. Moreover, many leasing specials require that the car be picked from dealer stock, which means you may not be able to special order a car at the advertised price. Sometimes, a dealer's "special" price may be subject to an unpublished discount, further complicating the deal.

Selling Price and Residual Value

When leasing a car, two key numbers drive your monthly payment: the selling price and the residual value. The residual value is the estimated worth of the vehicle at the end of the lease term, based on the car's condition and mileage. A higher residual value means lower monthly payments, as you're financing less of the car's depreciation. It's important to understand that while you may be able to negotiate the selling price, the residual value is often fixed by the manufacturer.

Beware the Money Factor

Leasing doesn't work like renting an apartment—you're not just paying for the car's depreciation. Instead, you're also paying the finance charges associated with leasing, known as the money factor. The money factor is the interest rate baked into the lease, and it can significantly impact your monthly payments.

Unlike traditional loans, the money factor is not presented as an interest rate (APR) but is written as a small decimal number, usually in five places. For example, a money factor of .00238 is equivalent to an APR of 5.7%. This seemingly insignificant number can have a big impact on your monthly payments. Even small changes to the money factor can alter your lease payments by hundreds of dollars over time, so it's essential to understand it.

Dealers often mark up the money factor and keep the difference as profit. Be sure to ask what the rate is and whether it's negotiable. Although it's not as straightforward as financing, getting quotes from outside banks or lenders can help you spot an inflated money factor.

Hidden Fees That Add Up

Leasing may seem affordable because of its low monthly payments, but you should be aware of the various fees that can quickly add up. Here are some common, often unavoidable, fees that might be included in your lease:

1. Acquisition Fee: This is a bank fee that typically ranges from $500 to $1,000 and is added to your lease contract.

2. Disposition Fee: Charged when you return the car at the end of the lease, this can also cost $500 to $1,000.

3. Security Deposit: If your credit isn't stellar, you may be asked to pay a security deposit, which is refundable at the end of the lease.

4. Advertising Fees: Dealers often include advertising fees to recover their marketing costs. These fees are rolled into your lease payment and can run several hundred dollars.

5. Conveyance Fee: While you won't pay a destination fee, a conveyance fee of a few hundred dollars may be charged to handle paperwork and transport.

6. Sales Tax: Depending on where you live, sales tax can be significant and may be based on the full purchase price of the car—not the depreciated amount you're actually paying during the lease term.

Although these fees are typically non-negotiable, knowing about them in advance allows you to factor them into your overall cost. Some fees, such as advertising or acquisition fees, may be negotiable, especially if you're buying or leasing from a dealer with flexible terms.

Additional Costs to Watch Out For

While leasing offers low monthly payments, the total cost of the lease might not be as straightforward as it appears. In addition to the standard fees and the money factor, you could be responsible for any damage to the vehicle, excess mileage charges, or modifications beyond the factory specs. Make sure you follow the terms of the lease agreement to avoid these additional costs.

Also, check your state's tax laws. Some states require sales tax on the entire vehicle price, while others tax you only on the payments you make during the lease. Certain states, like Connecticut, add a luxury tax for vehicles priced over a set amount, so it's important to understand how taxes affect the overall price.

Final Thoughts

Leasing can be an attractive option if you're looking for lower monthly payments and the ability to drive a new car every few years. However, the true cost of leasing is far from transparent, with hidden fees, high money factors, and potential changes to the deal that could surprise you.

Always review the terms carefully, ask for a breakdown of all costs, and make sure you understand the money factor before agreeing to a lease. With this knowledge in hand, you can better negotiate the terms of your lease and ensure you're not overpaying. Remember, just because a deal sounds good on paper doesn't mean it's the best one for you in the long run.