The collection belongs to Swedish ABBA fan Thomas Nordin and is expected to fetch some SEK 830,000.
Nordin told Radio Sweden that he started his collection 39 years ago, at the age of nine, when he received the single Waterloo from his mother. With his fiftieth birthday approaching Nordin felt it was time for a change, he said.
"Interest in the auction has been huge since we announced it in late June," Stockholm Auction House curator Beata af Donner told AFP.
But not many visitors have come to view the objects in person.
"People look [at the items] on the internet. Some potential buyers don't come but rather ask for information. They call and take a chance by placing a bid ... We have a fair amount of tourists [who visit in person] also," af Donner said.
Among the rarities to go under the hammer are two maxi singles that ABBA recorded in Swedish but never released commercially: Hovas Vittne - made for their manager Stig Anderson's fiftieth birthday in 1981 - and Saang till Goerel, recorded for ABBA's record company assistant Goerel Hanser's thirtieth birthday in 1979.
Nordin, a 48-year-old tailor, told Radio Sweden that he is keeping three pieces of memorabilia back for himself. He amassed his collection through friends, other collectors, book shops, record shops and the internet.
Other highlights from the collection include a pair of ABBA clogs made exclusively for the American market, ABBA soaps and dolls and a large collection of clippings, books and posters.
In 1999, the entire collection was loaned out to "ABBA The Exhibition" at Nordiska Museet in Stockholm. The sale comes just three months after the much-hyped opening of the ABBA museum in Stockholm.
Nordin told AFP that the ABBA museum may bid on selected items, but is not interested in buying the entire collection.
The collection is being sold in 450 lots on Saturday and Sunday.
Nordin told Radio Sweden that he will now enjoy the empty space in his apartment and take a long vacation.