Improve current home
This side includes your estimated renovation or build improvement cost plus the contingency allowance you select. It can be used for extensions, layout changes, whole-home upgrades or large room-focused projects.
UK renovate or move planning calculator
Build vs Buy Calculator
Compare improving your current home with moving or buying a more suitable property, using renovation cost, contingency, moving allowances, property price gap and lifestyle assumptions.
A build vs buy decision is not only a cost comparison. It also depends on disruption, space needs, location preference, property availability and how certain your project costs are.
This calculator provides planning estimates only. It is not mortgage advice, financial advice, tax advice, legal advice, valuation advice, estate agency advice or investment advice.
Calculator
Compare improving your home with moving
Enter your own planning figures. For buying, selling, borrowing, tax or legal decisions, check the assumptions with qualified professionals.
Comparison guide
What the Build vs Buy Calculator compares
The calculator compares two broad scenarios. The first is improving the home you already own or live in. The second is moving to, or buying, a more suitable property.
Move or buy elsewhere
This side includes the property price gap between your current home and target property, plus user-entered moving allowances such as estate agent fees, stamp duty allowance, legal fees, survey costs, removals and mortgage or product fees.
The calculator does not calculate stamp duty automatically because rules vary by UK nation, buyer type and current legislation. Enter your own allowance or check with a qualified adviser.
Methodology
How build vs buy is calculated
The calculation compares the cost of improving the current home with the planning cost of moving to a target property. A positive difference suggests improving appears financially lighter in the selected scenario. A negative difference suggests moving appears financially lighter.
Close results need more checking. When the two scenarios are similar on cost, lifestyle, disruption, quote accuracy, mortgage checks, legal advice and tax assumptions may matter more than the headline figure.
Review CostIntel’s wider approach on the methodology page, the pricing data page and the guide to how costs are calculated.
Original CostIntel insight
Decision Pressure Flag
The Decision Pressure Flag shows whether the comparison is mainly cost-driven, lifestyle-driven or too close to call without more detail.
Why the flag looks beyond cost
A renovation may appear financially lighter, but low disruption tolerance can weaken that option. Moving may appear more expensive, but urgent space needs may still make it more practical.
What can change the result
Suitable home availability, location preference, the accuracy of renovation quotes, mortgage assumptions, tax position and time horizon can all change how useful the headline cost comparison is.
Moving costs
Moving cost allowances to include
Moving costs can be easy to understate. The calculator includes common allowances, but your own situation may include extra costs.
Transaction allowances
Include estate agent fees, stamp duty or land transaction tax allowance, legal and conveyancing fees, survey costs and any mortgage or product fee allowance.
Practical moving costs
Include removals, storage, temporary accommodation, cleaning, overlap costs or short periods of double running costs where relevant.
Professional checks
This calculator does not provide tax, legal, mortgage or financial advice. Moving cost rules and obligations can vary, so check important figures separately.
Scope
What the estimate includes and excludes
This calculator helps structure a comparison. It cannot replace property-specific checks, lending advice, legal advice or a full renovation quotation process.
| Included in the calculator | Not included in the calculator |
|---|---|
| Current estimated property value | Professional property valuation |
| Target property value or expected purchase price | Mortgage affordability assessment |
| Renovation or build improvement cost | Lending recommendation |
| Renovation contingency | Full tax calculation |
| User-entered moving allowances | Legal advice |
| Lifestyle and disruption settings | Survey findings or hidden defects |
| Market availability setting | Guaranteed property availability |
Professional review
When this comparison needs professional review
Use this calculator to structure the comparison. Do not use it as the only basis for a property, mortgage, tax, legal or major family decision.
Get professional advice when buying or selling property, remortgaging, calculating stamp duty or land transaction tax, using savings or borrowing to fund work, planning structural changes, dealing with leasehold restrictions or comparing homes in different UK nations.
Input quality
How to make the comparison more useful
Use realistic property search figures, recent renovation quotes, a sensible contingency and moving allowances that match your situation. If the comparison is close, small changes to one input can change the result.
For renovation-side costs, the Renovation Budget Planner can help structure the improvement budget before you compare it with moving.
Practical scenarios
Example build vs buy scenarios
These examples show how the calculator can be used. They are not recommendations to renovate, move, borrow, buy or sell.
Growing family considering an extension
A homeowner can compare the cost of extending with the price gap and moving allowances involved in buying a larger property nearby.
Priced out of a preferred area
If suitable homes are limited or expensive, improving the current property may be worth comparing even when the renovation budget is high.
Low disruption tolerance
Renovation may appear financially lighter, but a household with low disruption tolerance may still need to treat moving as a serious option.
Close cost comparison
If the two scenarios are close, quote accuracy, mortgage checks, legal advice and lifestyle fit become more important than the calculator result.
Related tools
Related project planning and cost tools
Use these tools together to compare renovation cost, value assumptions, budget risk and wider property decisions.
Project Planning Tools
Return to the hub for all CostIntel homeowner planning calculators.
View Project Planning ToolsRenovation Budget Planner
Build a structured renovation budget before comparing it with moving.
Plan a renovation budgetProperty Value Uplift Calculator
Estimate possible value uplift from renovation type, property type and market setting.
Estimate property value upliftRenovation ROI Calculator
Compare renovation cost with estimated potential value uplift.
Estimate renovation ROIKitchen renovation costs
Estimate kitchen cost before adding it to a renovation plan.
Use the kitchen cost calculatorBathroom renovation costs
Build a bathroom cost estimate for wider renovation planning.
Use the bathroom cost calculatorPlastering and preparation
Estimate preparation costs before comparing improvement and moving scenarios.
Use the plastering cost calculatorPainting and decoration
Estimate decoration costs for refresh or resale preparation plans.
Use the painting cost calculatorFAQs
Build vs Buy Calculator FAQs
Is it cheaper to renovate or move?
Sometimes improving the current home appears financially lighter, but this depends on renovation cost, contingency, the property price gap, moving costs and lifestyle needs. The calculator shows a planning comparison only.
What costs should I include when comparing moving and renovating?
Include renovation or improvement costs, contingency, the gap between your current and target property, estate agent fees, stamp duty or land transaction tax allowance, legal fees, survey costs, removals and mortgage or product fee allowances.
Does this calculator include stamp duty?
It includes a user-entered stamp duty or land transaction tax allowance. It does not calculate stamp duty automatically or provide tax advice.
Is this mortgage or financial advice?
No. The calculator provides planning estimates only. It is not mortgage advice, financial advice, tax advice, legal advice, valuation advice or investment advice.
When does moving make more sense?
Moving may be worth comparing when the current home cannot meet your space or lifestyle needs, disruption tolerance is low, suitable homes are available and the cost gap is manageable. A professional adviser should check major financial assumptions.
When does renovating make more sense?
Renovating may be worth comparing when you prefer the current location, suitable homes are hard to find, the improvement cost is lower than the moving scenario and the household can manage disruption.
Why can a cheaper option still be the wrong fit?
Cost is only one part of the decision. Space needs, timing, disruption, school or work location, market availability and long-term plans can outweigh a simple cost comparison.