A promotional tour is expected to begin next month and Newton told The Associated Press he hopes to offer the first public tours by February.
Visitors will be able to survey the singer's collection of European antiques and celebrity mementos - including Nat King Cole's watch, a Johnny Cash guitar and a champagne glass used by Frank Sinatra to toast Newton.
"It's going great," Newton said Tuesday. "It should be open by January or February."
The attraction was initially slated to open in December, but Newton said the project was delayed because construction permits were not approved as quickly as planned.
A museum, theater, visitors' center and other attractions were being added to the property. And revised building plans submitted last month call for expanding the museum space and theater, where Newton will perform at least occasionally.
Newton received permission last year to turn his lavish home into a tourist venue after a bruising battle in which his neighbors said they didn't want tour buses invading the largely residential neighborhood where the "Danke Schoen" singer built his 10,000-square-foot home decades ago.
The 40-acre estate features South African penguins, Arabian horses, Impressionist paintings by Pierre-Auguste Renoir and 17th-century antiques collected from European castles. Some of the keepsakes were gifts from the mentors and friends who helped make Newton famous, including Sinatra, Elvis Presley, Bobby Darin and Jack Benny.
Newton, his wife and their daughter are expected to move into a smaller house on the property, ceding the main house to the public.
Newton has said the tourist attraction will be both a showcase for his collections and a tribute to some of the performers that made Las Vegas a celebrity haven. The revamped estate is expected to employ more than 400 people at a time when unemployment in Nevada is above 13 percent, the highest rate in the nation.