If a Quote Is Dramatically Cheaper, Something Is Missing.
Written by Mal MiddletonDirector, Forsyth Construction Surrey Ltd
If a Quote Is Dramatically
Cheaper, Something Is Missing.
A practical UK homeowner guide to understanding extension quotes, avoiding budget shocks, and protecting your build investment.
The Cheapest Quote Is Rarely the Cheapest Build.
Construction quotes are not always comparable on face value.
Two builders can submit prices thousands of pounds apart — yet appear to be quoting for the same project.
In reality, differences often come from:
• Missing scope items
• Understated provisional sums
• Unrealistic labour allowances
• Incomplete structural specification
• Excluded finishes or services
These omissions rarely reduce final cost.
They simply delay when the cost appears.
The financial risk is not in the highest quote.
It is often hidden in the lowest one.
This guide breaks down how extension and refurbishment quotes are structured in the UK, and where financial risk commonly hides before a contract is signed.
• How to properly compare multiple builder quotes
• What provisional sums really mean in practice
• The most common missing items in domestic extensions
• How labour allowances are often understated
• The psychology behind dramatically low pricing
• Real-world examples from live structural projects
• Practical steps to protect your build budget
About the Author
Mal Middleton is the Director of Forsyth Construction Surrey Ltd, a UK-based construction company specialising in structural alterations and domestic extensions.
Over the course of his career, he has managed projects ranging from structural knock-throughs to complex multi-stage extensions. His experience includes coordinating specialist trades, sequencing structural steel installation, and guiding homeowners through the practical and financial realities of construction.
This guide has been written to help homeowners understand how quotes are structured, where risk can sit within pricing, and how to make informed decisions before committing to a contractor.
Protect Your Project Before It Starts.
A modest investment now can prevent significant financial mistakes later.