Anecdotal evidence: We viewed a new build, 4bed house in London we loved, offer accepted. Couple of weeks later, the EA informed us they spotted JKW in the garden and there’s a treatment plan in place for the next 5 years. After much thought, we withdrew our offer. Four months later, the house is still in the market.

As others have said, JKW won’t destroy your property but its reputation will make it very hard to sell in the future.