Note: This story has been corrected.

After 15 months of work valued at nearly $10 million, a downtown Longview landmark is set for its public debut.

Saigebrook Development next month is hosting a private grand opening of Alton Plaza, a 48-unit apartment complex inside the historical, renovated Petroleum Building. It's set for March 25.

“We are thrilled to be to this point and can’t wait for our first residents to move in this week,” Megan Lasch of Saigebrook Development said Thursday.

City of Longview officials and other guests will get views inside the 66-year-old, 61,000-square-foot building that at various times in its history has been a parking garage, then a combination garage and office building — and for many recent years a derelict and crumbling structure that was near demolition due to safety concerns.

But contractors have rehabbed and renovated the Petroleum Building under a $9.962 million project that included state tax credits and a $600,000 loan from the city.

“It‘s a drastic improvement from the graffiti-filled building it once was,” Lasch said. “As of Monday, we have only six units left to lease.”

The apartments serve residents and families who earn from 50% to 60% of the area’s median income, which is just less than $60,000.

Four apartments are set aside for residents at 30% of the area median income, and another 15 units are being leased at market rate.

Anyone interested in applying for residency at Alton Plaza should call (903) 236-5022 or email .

The Petroleum Building is recognized as a local historical landmark by the city.

Saigebrook Development used the building’s historical significance to get more than $1 million in tax credits through the Texas Department of Housing and Community Affairs — all part of more than $5.5 million in federal and state tax credits devoted to financing the project.

In August 2018, the Longview City Council agreed to extend a $600,000 loan to Saigebrook to make up for a shortfall in funding the renovations.

The loan is to be repaid at 1% interest, resulting in about $93,000 in interest.

Without the renovations, the city might have spent more than $1 million to demolish the building into a concrete lot, Development Services Director Michael Shirley has said.

It’s only the latest for Saigebrook in Longview. Within the past seven years, the firm has opened three residential developments in the city — Alton Plaza at the Petroleum Building, and Amberwood Place and Edgewood Place — bringing 200 new residential units into the city.

Jimmy Daniell Isaac covers the city of Longview and Gregg County. Follow him on Twitter: @jimmyisaaclives.