When Jimi Hendrix lived in a bohemian London flat in the 1960s, he had little need for its kitchen as he had meals sent up from Mr Love, a groovy restaurant on the ground-floor of his building.

While celebrities were downstairs, dining at heart-shaped tables and served by waitresses in hot pants, the American rock musician was upstairs, tucking into steaks and hamburgers.

Now receipts for those meals are among a vast archive of previously unseen material relating to Hendrix’s life and music to be exhibited for the first time at 23 Brook Street, the Mayfair Georgian building where he lived, which is now a museum.

One bill, covering food over a couple of months, totalled £32/16s/6d, which would be about £485 today. He particularly liked Mr Love’s American menu, once saying that the problem with English food is “you get mashed potatoes with just about everything, and I ain’t gonna say anything good about that”.

The restaurant receipts are part of a collection that brings to life a guitarist, singer and composer who pioneered the expressive, explosive possibilities of the electric guitar, in music that mixed rock, soul, blues and jazz. His great classics include Purple Haze, Foxy Lady and All Along the Watchtower. He died in 1970 aged just 27, after an apparent overdose.

Many of the documents to be displayed for the first time are the corporate records of Anim Records, the company that managed the Jimi Hendrix Experience and other acts. They include everything from contracts to calendars, recording historic performances and flight details, as well as invoices for the music equipment that helped shape his trailblazing sound.

While its founder, Mike Jeffery, was officially Hendrix’s manager, the day-to-day affairs were looked after by his personal assistant, Patricia ‘Trixie’ Sullivan, now 83. Between 1966 and 1973, she was booking sessions at recording studios, organising itineraries and negotiating contracts, while also accompanying the musicians on tours worldwide.

After Jeffery’s death in 1973, she collected material that bailiffs had left behind after entering his London office, more interested in its furniture.

She kept everything in four plastic trunks under her bed in Spain. When she returned to the UK, because her health was deteriorating, her grandson, Jonathan Garcia Sullivan, stored them in his shed in Dorset.

Now the material has inspired an exhibition that will be staged next month in the Handel Hendrix House, a museum in the actual homes of two of the greatest musicians who ever resided in London – George Frideric Handel, who lived at 25 Brook Street from 1723 until 1759, and Hendrix, who was at No 23, between 1968 and 1969. Mr Love’s space is now a fashion shop.

Handel Hendrix House – dubbed the home of “Baroque ‘n’ Roll” – has acquired many of the exhibits in the forthcoming show with the support of the National Lottery Heritage Fund.

The flat that Hendrix shared with his girlfriend Kathy Etchingham has been meticulously recreated. He once described it as the only place he felt truly at home. It was there that he entertained and collaborated with other icons of British 1960s rock music. On the stairs to his flat, George Harrison famously had to step over one of Hendrix’s other friends, who had passed out en route to the exit.

The new exhibits include letters, work permits and dry cleaning tickets for a striped suit and a gold jacket, among other psychedelic-inspired clothes, as well as phone bills totalling tens of thousands of pounds.

There are also Sullivan’s diaries, with notes that she made during Hendrix’s January 1969 tour of Germany. Of their Munster gig, she wrote: “One show only – great crowd nearly rioted – broke many chairs damage $250. Got pushed around as entered car.”

Claire Davies, the exhibition curator and deputy director of the Handel Hendrix House, said of the receipts and other documents: “They tell a really important story of this one little moment of domesticity in Hendrix’s life. He had a very difficult childhood and then, during his four-year career when he was based in London, he was staying with other people or in hotels. So when he was here at 23 Brook Street, it was the only place he called home and the only place with his name on the rent invoices.

“To furnish his flat, he bought high-end Persian rugs that in today’s money would be worth about £30,000, the receipts show. It’s a really interesting insight into what his life behind his rock star image looked like for this brief moment, but also how it could have looked if he had lived a little bit longer and then settled down properly.”

Sullivan told her grandson that Hendrix “was quite introverted” and “self-doubted himself a lot”, and that he was always playing his guitar when she visited his flat.

Garcia Sullivan said: “I’m sure my nan would have just bullied him into being confident … She described herself as his babysitter. So that’s how the receipts were collected, because she was trying to give some order to his life by paying for those things.”

The material reveals that Sullivan was “the absolute epicentre of everything that Hendrix and the Experience were doing”, Davies said. “She was clearly running the show. I’m not sure they’d have been able to do it without her.”

The exhibition opens on 19 June at 23 Brook Street.