Be careful when closing a deal with a rental apartment - what you read on online listings aren't always the truth.

While there are great landlords out there, there are also less-than-scrupulous ones who will try to take advantage of renters in ways that can make you end up paying more than you should. Is it a "newly renovated" unit? Wait until you actually get to see the unit and realize that the closest thing to a renovation is a new window type AC. The sad truth is, some landlords make their properties "attractive" by fudging the truth.

Here are 3 landlord lies that cost renters big according to Trulia:

They imply pictures never lie

You find this amazing apartment online and you are so happy to see that it is just the right space you are looking for. But wait...

"The old phrase 'A picture never lies' was said long before the invention of Photoshop and fisheye lenses," says Lucas Hall, chief "landlordologist" at Cozy.co. "An inexpensive fisheye lens can visually add 100 square feet to a room," he says. And that can be a big disappointment when you see the property in person.

This is considered false advertising and a reputable landlord would take the extra effort of using a wide-angle lens that would showcase the space but won't distort its actual size.

They tell big fish stories

"Misleading advertising is definitely an issue that hits our radar," says Joel Cohn, legislative director for the (Washington) DC Office of the Tenant Advocate.

This is brought about by more and more people who are doing "renting sight unseen." If you want to save yourself the headache of leasing an apartment that don't sit with your standards, never rent sight unseen. Have someone you trust personally inspect the unit if you can't do it yourself, but if not, don't ever sign an online document with an e-signature.

Also, be very careful with enticing rental ads you come across online. The most common one is advertising a neighborhood as a "short walk" to shopping and dining. "To my brother who lived in New York City and would walk 30 blocks a day, a short walk is 2-plus miles. To my grandmother who hasn't left her house in five years, a short walk is 10 feet to the restroom," says Hall.

So make sure to look for specifics such as "two blocks to the Metro" or "8-minute walk to the grocery store".

They break promises

There is something about landlords and repairs that is just almost always sure - they don't live up to it. To avoid ending up in a tenant's words against a landlord's situation, make sure to put everything in writing before you even sign the lease. If the landlord promises to do the repairs or do something about issues with security, "add language to your lease about the promised repair or security feature along with a specific time frame for completion," says Ron Leshnower of Fair Housing Helper.