A collection of artist LS Lowry's personal papers which reveal how much he sold his early works for are to go under the hammer.
The papers, which were dumped outside a scrap yard in Manchester in 1981, also include hand-written letters, expenses and income tax sheets.
Stephen Sparrow from Peter Wilson auctioneers said the collection was "effectively access to Lowry's bank statements".
The papers could fetch up to £800.
All the documents, which will be sold on Thursday, relate to the period 1959-1966.
One note reveals the artist's painting Old Houses - which is now worth £500,000 - sold for £45 in 1962.
Another work from the same year, Country Road Near Lytham, sold for £35. It was exchanged for more than £300,000 last year.
Mr Sparrow told the BBC the original sale prices were worth more than their small sum by today's standards.
"That was an awful lot of money - if you look at what you could've done for £35 in the 1960's, it's not too disproportionate [to his current selling figures]".
He added it was an "intriguing, fascinating assortment" of papers which give an insight into Lowry's life as a flourishing artist.
The documents were originally handed in to the police when they were found at the scrap yard in Ardwick.
As they were never claimed, they were handed back to the finder whose family have put the collection up for sale.
"It's always interesting to have further detail on someone's career," Claire Stewart, curator for The Lowry arts centre in Salford, told the BBC.
However Ms Stewart said, as the gallery had no acquisitions budget, it was not expecting to make a bid for the items.
She added: "We would be interested in keeping a record of it and it would be nice to have a look through them to find out any other information about the artist."