The pandemic-era low mortgage rates may have disappeared but what if you could still get rates below 5%?

Mortgage rates averaged 7.57% for a 30-year conventional loan this week, making an already unaffordable housing market for potential homebuyers worse.

But a new real estate start up is promising buyers the opportunity to find rates that are at least two percentage points below the market rate. The only catch? The loans on the homes they are looking to buy would need to government-backed.

Roam, a platform launched last month, connects sellers who have locked in low rates with potential buyers, through the process of mortgage assumption.

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How does an assumption of a mortgage work?

Mortgage assumption allows the seller of a home to pass along to the buyer an existing home loan, negotiated earlier at low interest rates. The buyer takes over the seller’s existing mortgage at closing in lieu of getting a new loan.

Currently, the only loans in the market with a standard qualifying assumption clause are VA, FHA and USDA loans, according to the National Association of Realtors.

How buyers, sellers and realtors benefit

Roam helps sellers, buyers, and real estate agents in today’s challenging housing market, says the company’s founder and CEO Raunaq Singh, who was instrumental in starting the mortgage arm at Opendoor, the iBuyer.

Singh declined to specify the size of his client base.

“It was clear that for the sellers, a large part of what was preventing them from moving forward and wanting to list their homes was ‘I don't know if I want a bunch of people rifling through my stuff if it's not even clear the homes are going to sell because the rates are so high,” he says.

Most homes on the platform have a mortgage rate of 4%, though they could be as low as 2% and as high as 5.5%, according to Singh. Buyers will pay 1% of the sales price in the form of closing costs.

Roam estimates there are approximately 4.4 million homes with assumable mortgages that fit their criteria: the outstanding loan is at least 50% or higher and if the outstanding loan amount is between 50-75% loan to value, the rate must be at or below 4%; if the loan to value is 75% or higher, the rate must be at or below 5.5%.

However, locating properties with assumable mortgages remains challenging, as they often go unnoticed, and both buyers and sellers need more information. Roam, which is currently in five markets -- Arizona, Colorado, Florida, Georgia and Texas -- enables homebuyers to easily search for homes with mortgages eligible for assumption.

The median price range of a home on the platform in these markets is $380,000. For the buyers, the Roam website shows how they could reduce their monthly mortgage payment by close to half compared to purchasing a home at today's prevailing rates.

For example, a home in Gainesville, Georgia, listed at $350,000 can be assumed for a 3.125% interest rate with a $35,000 down payment. Then monthly mortgage cost would come to $1,359 as opposed to $2,381 at the current mortgage rate of 7.5%

It also could be an attractive option for the agents who are grappling with low transaction levels, and the platform can help generate more sales.

Swapna Venugopal Ramaswamy is the housing and economy reporter for USA TODAY. Follow her on Twitter @SwapnaVenugopal