Rent will be going up for some families living in public housing after Congress mandated flat-rate rents be 80% of the fair market rate.

"It's supposed to be a place, a stepping stone to get on your feet and how are they going to get on their feet when they're charging rent of $500 to 600?" said Lauren Smith.

Smith lives in the East Lake homes, where those paying a flat rate will soon see a higher bill for rent.

"No this is supposed to be a stepping stone to move out, you can't save anything paying flat rate," said Smith.

She says while many choose to pay a percentage based off their income, others who make a little more money are able to save more of it by paying the flat fee.

On September 1, that may not be the case.

We looked at the numbers to see the difference of what the new flat rate would be versus the old.

A one bedroom apartment at East Lake, currently rented out for $390, will go to $437 a month; a $47 increase.

That may seem small, but take a look at the 3 bedroom at East Lake, currently sitting at $515 for a monthly flat rate, will rise to $738 a month, a $223 increase.

"I think it's outrageous, especially with how many killing there are out here every day, can't even let your kids play," said a neighbor who wished to remain anonymous.

The Chattanooga Housing Authority's website says some may not see rate spike as high, saying they are capping the increase to 35% for families already participating in the program.

But those who sign up after September first will pay the whole new amount.

Smith said if the rent goes up too high many may find somewhere else to live, where she says will have better amenities.

"I think the ones who can afford to move, will move," said Smith.

Current program participants who pay the flat rent amount will be faced with a few options.

They can either pay the new flat rate price or switch to the income-based rental amount.

The rates will vary on location and size of the apartment.

You can find that information by clicking here.