Caroline Jones, 47, from Harpenden in Hertfordshire, began Knickers Model's Own to raise money for Cancer Research UK in memory of her mother Mary Benson, who died of breast cancer last October.
About 1,000 items of clothing and accessories went on sale at Harpenden Public Halls on Wednesday.
The sale raised just over £2,600 to add to more than £26,000 raised to date.
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Mrs Benson had been a volunteer at the charity's Harpenden shop for 13 years.
Mother-of-three Ms Jones started volunteering as a window dresser soon after her mother died and on New Year's Eve last year decided she would post a photograph every day on social media of her wearing a different outfit.
She hoped to raise £1,000 in a year, but her daily posts became so popular she increased her fundraising target to £36,500 - or £100 a day.
She recently won a prize for the most creative fundraiser of the year.
At the one-off event on day 308 of her campaign, she modelled some of her outfits on the catwalk before the audience was invited to buy their favourite pieces - which raised a total of £2,693.25.
The few unsold items - which amount to about two clothes rails - will be sold through the CRUK Harpenden shop.
"I have mixed feelings about the sale," she said.
"Obviously I am very attached to some pieces as they all hold memories for me. Seeing other people touch them is strange.
"But my intention was always to sell the collection on, with the funds going to my campaign."
She felt her initial £1,000 target was "ambitious" and described the response as "incredible".
"The money raised [so far] will pay for a year's bursary for a researcher," she said.
A woman who sported a different charity shop outfit every day for the last year has decided to sell them all.