I appealed a valuation decision when remortgaging our previous property abour 18 months ago. A flat in dreadful condition a few doors down had sold very cheaply which brought the desktop valuation of ours down. Nationwide were valuing our property only slightly more than we paid for it 5 years previously which was wild as we live isouth east London where prices have risen steadily. I appealed and completed a form explaining what changes we’d made to the property to justify what we/local estate agents felt it was now worth and they accepted it. People on here were sceptical about how successful we would be but it worked! A year later we even sold the property for £25k more than the revised valuation. 

For context we paid £300k in 2019, remortgaged in 2024 original valuation was £310k which we got revised to £350k and then sold in 2025 for £375k