In need of renovation: how to estimate the works before bidding
Of 13,474 auction properties with an analysis of the appraisal report, 2,521 are flagged as in poor condition or in need of renovation: one in five.
It is the item that weighs most after the price, and the only one that no procedure document quantifies for you. The appraisal report describes the condition — “windows and doors in poor condition”, “systems not up to standard”, “requires maintenance work” — but does not give a quote. You have to put that number in yourself, before bidding, and getting it wrong is the most common way of turning a 30% discount into breaking even.
The three bands, and what sets them apart
They are not official categories, but they help put things in order.
Needs freshening up. Systems up to standard and working, bathroom and kitchen usable, windows and doors in order. It is a matter of painting, a few replacements and a deep clean. It is the only band in which you can move in almost straight away.
Needs renovation. Systems to be redone, bathroom and kitchen to be redone, windows and doors to be replaced, floors to be replaced. No structural work. It is the most common band among auction properties and also the most underestimated, because to the eye the flat “looks fine”.
Major renovation. The internal layout is changed, work is done on the floor structures or the roof, everything is redone. Here you need a design, building permits, long timescales and a proper contractor.
The difference between the second and the third cannot be seen during the viewing. It is seen when a technical professional looks at the floor structures, the roof and the condition of the walls.
The items people forget
Anyone making a quick estimate thinks of the bathroom, kitchen and floors. It is other costs that blow the budget.
The systems. Bringing the electrics and plumbing of a flat up to standard means chasing the walls, and therefore replastering and repainting every room. Redoing the electrical system is not an isolated job: it drags half the home along with it.
Heating. Boiler, radiators, flue. If the flue is not compliant or does not exist, things get complicated and sometimes involve the condominium.
Windows and doors. They are a big item and are always underestimated, because you only realise it when you count the windows.
Disposal. Emptying a flat full of stuff, throwing out the old bathroom fittings, the removed floors, the windows. Transport to the tip is paid by weight, and on a complete renovation it is not a negligible sum.
Paperwork. CILA or SCIA depending on the works, site supervision, a design if needed. And if there are irregularities to regularise, they come before the works, not after.
Time. Six months of building work are six months in which the property earns nothing and, if you are renting, you pay twice.
How to estimate properly
The method that works is banal and almost nobody applies it: bring a technical professional or a contractor to the viewing.
You can ask the custodian for a viewing of the property and you can bring someone with you, by agreeing it in advance. Half an hour of a surveyor or a heating and plumbing engineer inside the home gives you an order of magnitude no desk estimate can give, because they look at things you do not: where the drains run, what type of floor structure there is, whether the boiler can be replaced where it is or has to be moved.
It is the investment with the highest return in the whole due diligence. It costs little and tells you whether the deal exists.
If you cannot bring anyone, the minimum is to photograph everything — electrical panels, boiler, bathrooms, windows and doors, damp patches, ceilings — and have someone who knows the subject look at the photos. It is worse than an inspection, but much better than nothing.
The sum that counts
The only sensible comparison is not between starting price and appraisal. It is this:
award price + taxes and costs + works + months of waiting, against what the same property in good condition costs on the market.
If the two numbers are similar, the auction discount has only served to buy you the job of renovating. Sometimes that is perfectly fine — if you do the work yourself, or if you want the home exactly the way you want it. But it must be decided knowingly.
Then there is a rule of thumb worth bearing in mind: renovation costs are always underestimated, and almost never by a little. Anyone who budgets a 20% contingency on top of the quote rarely regrets it.
Tax benefits
Tax deductions for building renovation change often, in both rates and caps, and it is worth checking the current rate before putting it into your sums instead of assuming what applied the year before.
Two things remain stable and matter: the benefits depend on precise requirements relating both to the person and to the property, and they must be planned before starting the works, because some require prior notifications. Asking your accountant after paying the first invoice is the classic way of losing them.
Frequently asked questions
Does the appraisal report say how much the works cost? Almost never. It describes the condition. Some experts give a rough estimate: when there is one, it is a starting point, not a quote.
Can I view the property with a contractor before bidding? Yes, by agreeing it with the custodian. It is the most useful thing you can do.
Is it worth buying a property in need of renovation at auction? It depends on whether the full calculation — price, costs, works, time — stays below the market value of the finished property. The initial discount alone tells you nothing.
Can I start the works immediately after the award? No. You need the transfer decree, and if the property is occupied, it must first be vacated.
What if I find out afterwards that the works cost twice as much? That is the risk you took. There is no guarantee and no withdrawal: the bid was irrevocable and the award is final.
Data as at 15 September 2026, on active properties with an analysis of the appraisal report available. The filter returns “the lots where our analysis flagged poor condition”, not all those that are in poor condition. The tax information is indicative and is not a substitute for professional advice: check the rates in force.