Property development guides

Plain-English guides to the numbers and rules behind UK property development — from working out GDV to what a loft conversion actually costs.

What Is GDV and How Do You Work It Out?
What gross development value means, how to work it out from sold prices, and where people get it wrong.
Stamp Duty When You're Buying an Additional Property or a Development
How the additional property rates work, with a worked example and the reliefs worth knowing about.
What Is Residual Land Value and How Do You Work It Out?
How to work out the most you can pay for a site and still hit your target profit.
What Profit Margin Should You Aim For on a Property Development?
Profit on GDV versus profit on cost, what to aim for, and why the sale price hurts more than the build.
How Much Does a Loft Conversion Cost in the UK?
Typical costs per square metre by conversion type, how location changes it, and what people forget to budget for.
What Is an Article 4 Direction, and Why Does It Matter for HMOs?
How Article 4 removes permitted development rights, and why concentration limits are usually what stops an HMO.
What Does It Cost to Build or Renovate Per Square Metre in the UK?
Typical rates by job type, with and without a builder running it, plus how much location changes the number.
How Do You Know if a Property Deal Stacks Up?
The order to run the numbers in, what people forget, and the check most people skip.
What Does It Cost to Convert a House Into an HMO?
Why the range is so wide, what the big cost items are, and the planning rules that stop most schemes.
What Does It Cost to Convert a House Into Flats?
Why per square metre overstates it, the real cost items, and the planning and legal side people forget.
Development Finance Explained
How bridging and development finance actually works, what it costs, and why delays hurt more than anything else.
What Is a Development Appraisal?
What an appraisal actually does, the costs it has to include, and why the non financial checks matter as much as the numbers.

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