We've all made the mistake of signing on the dotted line and getting into a bad deal.

Perhaps a salesperson talked you into buying something you weren't really comfortable owning. Or maybe you took out a home-equity loan and later had second thoughts.

No matter the situation, the end result is the same: You have a bad case of buyer's remorse and wonder what, if anything, can be done.

Fortunately, there are many ways to unwind a transaction you've come to regret. Here's how to get out of a bad deal on four common purchases and borrowings.

Your car

Most of the time when you buy a car, you're either financing or leasing. If you finance your car and change your mind after signing a contract, you're still stuck with it unless the car has mechanical problems. In that case, you might have recourse via your state's lemon laws.

With a leased vehicle, though, you have far more options — even if you simply changed your mind.

Scot Hall, executive vice president of operations at Swapalease.com, estimates that at least 50 percent of people who lease cars experience buyer's remorse at some point during the contract.

"People might not be happy with the deal for any number of reasons," Hall says. "Financial difficulties may arise or there may be a change in family circumstances."

For older Americans, Hall says it's not uncommon for them to experience a kind of "empty nester syndrome in reverse."

"Someone with a minivan might have their last kid who just graduated from college, and now they want a two-seater," Hall notes.

Swapalease.com helps facilitate lease transfers online by matching people who want to get out of their auto leases with others who are looking to get into lease agreements. Hall says that in most cases the lease can be transferred immediately, whether you're one week, one month or even one year into the lease. All the negotiating — including how to pick up or drop off a car and whether any money needs to change hands — is done between you and the other party. Swapalease.com simply acts as a kind of middleman, handling the paperwork and helping you make sure you're following the leasing company's guidelines.

Feeling tied up by a deal? You can often get a refund, credit or exchange after a change of heart. — GSO Images/Getty Images

According to Hall, nearly every major carmaker — including General Motors, which offers such brands as Buick, Cadillac, Chevrolet and GMC; luxury brands such as BMW and Mercedes; and others — has fully assumable, transferable leases.

"So the person who had the lease walks away clear and free," Hall says.

Your mortgage

Did you refinance your mortgage or tap into your home equity but now you wish you hadn't? You can unwind the deal under certain circumstances — but you'll have to act fast.

Under the Truth in Lending Act, existing homeowners (not home buyers) have the "right of rescission," which means they can change their mind for any reason if they don't want to stick with a refinanced mortgage or a home-equity loan they've already signed.

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