The 1st Warfield Guide Group has stored camping kit in a shipping container at Moss End Farm for about 30 years, free of charge.
However, Guider Lucy Young has been told the group will have to pay rent from next month – which could cost more than £1,000 a month.
She said: “I can’t believe it. It’s not the fact of moving, it’s the notice issue.
“We’re a charity and do a nice bit for the community.
“Some of the stuff is going to have to be dumped. Some of it is quite old so that’s not the end of the world but there is other stuff we haven’t used for a few years but there will come a time when we need it.
“We want to hang on to it because you never know when you might need it.”
Mrs Young said she plans to write to Bracknell Forest Council to see whether it can do anything to help, but added the group has limited funds.
She said: “We have incredibly generous support from Warfield Parish Council but we are looking for somebody else to also be generous and helpful to us. Can anyone help us at all?
“I’ve had some kind offers from parents but there’s such a vast amount of stuff there. I’ve got some of the tents out and put them in my own garage but that’s now full.
“My biggest concern is we have got a marquee which cost about £4,000 and it needs somewhere dry and without mice.”
She added any temporary solutions would be gratefully received but said the situation will “run and run” until a permanent home can be found.
Alf Hyde, maintenance site manager at Moss End, said the situation was unavoidable. He said: “It was a hard conversation to have but the units are being taken off the site.
“To keep one of the others for them we would have to charge a normal rental price which is about £300 a week.”
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