The panels were found in 1953 behind coarse linen where they had been hidden probably for centuries
People are being invited to view a set of rare 15th Century religious wall paintings for what could be the last time.
A £240,000 appeal to buy a Grade I-listed cottage in Hertfordshire and save the seven panels has not yet raised enough money.
The Dacorum Heritage Trust said about £40,000 had been pledged.
The co-owner of the cottage in Piccotts End said she may now have to apply for a change of use to residential.
The cottage is open to the public until Sunday as part of the National Heritage Weekend but it could be the last time visitors get access.
The murals, thought to have been painted in about 1470, were found in 1953 by the cottage's then owner, Arthur Lindley, behind coarse linen, where they had probably been hidden for centuries.
They feature scenes such as Jesus' baptism, and depictions of St Catherine of Alexandria, St Peter and St Margaret.
'Additional funding'
Co-owner Karen Murphy and her business partner bought the conjoined cottage, which was once two homes, between them, in 2011, specifically to find a way for the paintings to be brought into public ownership.
The murals include scenes such as Jesus's baptism, and depictions of St Catherine of Alexandria, St Peter and St Margaret
They gave the heritage trust, which had been trying to purchase the property for about 20 years, time to raise the money to buy it and open a permanent visitor centre.
An appeal was launched last year and trust chairman Roger Hands said he was still "optimistic" and was looking to get the remaining funding from Dacorum Borough Council.
"I'm still hoping we will receive additional funding but I admit I've spent two or three years saying this without success," he said.
A council spokesman said the trust currently received a £58,000 annual grant from the council and it had had "no requests or applications for any further grants".
Ms Murphy said: "We may have to go for change of use to residential.
"This could be the last time they are available to be viewed by the public."
The murals are housed in the two cottages on the right, the other two have been sold for residential use
History of the cottage
Believed to have been used as a house for pilgrims between Ashridge and St Albans Abbey
After the Reformation the building was converted to a Tudor house then four cottages in the early 1700s
In 1825, Sir Astley Paston Cooper, surgeon to George IV founded the West Hertford Infirmary on the site to treat the poor - believed to be England's "first cottage hospital"
It was then occupied by master dyer Josiah Wright who is said to have foiled an assassination attempt on Queen Victoria on The Mall in 1840
Source: Dacorum Heritage Trust
- Published13 March 2014
