How to Calculate True Profit on an Auction Property
How to Calculate True Profit on an Auction Property
It's easy to get excited when you see a house listed £50,000 below market value. But the real question is: how much will you actually make?
The Common Mistake
New auction buyers often calculate profit like this:
£200,000 resale – £150,000 purchase = £50,000 profit
That's wrong. By a lot.
The Real Calculation
True profit means subtracting every cost from your gross margin. Here's what most people miss:
1. Auction Fees
These vary by auctioneer but typically include:
- Buyer's premium: 1–2.5% of the hammer price + VAT
- Administration fee: £300–£1,000
- Commission: sometimes charged to the buyer instead of the seller
Always check the special conditions in the legal pack.
2. Stamp Duty Land Tax (SDLT)
Stamp duty applies to the hammer price plus any buyer's premium. For a £150,000 purchase:
- Up to £125,000: 0%
- £125,001 to £250,000: 2%
- Plus 3% surcharge for second homes and buy-to-let
On a £150,000 investment property, that's £4,500 in stamp duty alone.
3. Legal & Professional Fees
- Solicitor: £800–£2,000
- Surveyor: £400–£1,500
- Mortgage/broker fees: £500–£1,500
4. Refurbishment Costs
This is where budgets blow up. A "light refresh" can turn into a full renovation once you start pulling things apart. Always add a 15–20% contingency.
5. Holding Costs
If you're not selling immediately, budget for:
- Mortgage/bridging interest
- Council tax
- Utilities
- Insurance
- Maintenance
6. Selling Costs
Don't forget the exit:
- Estate agent fees (1–2% + VAT)
- Conveyancing on sale
- EPC certificate
- Staging/marketing
A Real Example
| Item | Amount |
|---|---|
| Purchase price | £150,000 |
| Buyer's premium (2% + VAT) | £3,600 |
| Stamp duty (investment) | £4,500 |
| Legal fees | £1,200 |
| Refurbishment | £20,000 |
| Holding costs (6 months) | £3,500 |
| Selling costs | £4,200 |
| Total costs | £187,000 |
| Resale value | £200,000 |
| True profit | £13,000 |
That £50,000 "bargain" is actually a £13,000 profit — and that's before tax.
How BelowHammer Helps
Our built-in profit calculator factors in auctioneer fees, stamp duty, legal costs, refurbishment, and selling expenses. Enter the numbers from the legal pack and get an accurate profit estimate in seconds.
Bottom Line
The best auction buyers aren't the ones who find the cheapest properties. They're the ones who know exactly what the true numbers are. Do the full calculation before you bid — not after.