Works and renovation

Building the renovation budget of an older property from abroad: lots, contingency, phasing and tracking

A renovation budget for an older property is built by lot, never as one global figure, with a contingency set aside before the very first quote: in an old building, invisible hazards are the rule. From abroad, where you cannot pop in to see what a lining hides, that discipline counts twice. This dossier details the lots, the contingency, the phasing and the tracking of commitments through to handover.

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The Saint-Bénézet bridge of Avignon over the Rhône, with Mont Ventoux on the horizon — Avignon, Provence

By Jean Mascla, founder of Home Select Updated 24 October 2026 · 8 min read

Why break the budget down by lot rather than one global figure?

A global figure is appealing: it gives the illusion of a simple frame. But it says nothing about what you are buying, it makes quotes impossible to compare and it hides the trade-offs. The day a surprise appears, you no longer know which line should pay for it, or what to sacrifice to cover it.

Breaking the budget down by lots answers these three weaknesses. It makes quotes comparable, since every tradesman prices an identical scope, described in a single brief. It makes trade-offs possible, because you can move the boundary between the essential and the desirable lot by lot, without touching the rest of the project. And it keeps the follow-up readable: at any moment, you know which share of the budget is committed, paid, or still to pay.

The structure is stable from one project to the next: structural work, electrics, plumbing, heating and ventilation, finishes, and one last line that is far from the least important, the contingency for surprises. It is the common foundation of the Works and renovation dossiers, and the framework we suggest you follow. For the acquisition costs that surround the works, the notary fee simulator completes this framework. One line is almost always missing from this foundation: the damage-to-works insurance, compulsory as soon as the works fall under the ten-year guarantee.

What each lot contains, and its hazard

A lot is a package of works entrusted to one trade, with its materials, its constraints and its risks. Here is the reading grid, with the typical hazard to watch on every line.

Lot	What it includes	Typical hazard
Structural work	demolition, partitions, masonry repairs, openings	floor or load-bearing walls to reinforce, degraded masonry discovered on opening-up
Electrics	consumer unit, circuits, sockets, lighting, earthing	ageing buried circuits, ducts to recreate, protections to upgrade
Plumbing	water supply, drainage, taps, sanitary fittings	embedded pipework to replace, blocked or worn drains
Heating and ventilation	heat production, emitters, ventilation network	flues to clean or reline, radiators to replace
Finishes	painting, floors, joinery, wall coverings	surfaces needing more preparation than planned, doors to refit
Contingency	a separate reserve, fixed in advance and unallocated	damp, wall linings to redo, hidden services

The last line reads like the others: a scope, a rule of use, a discipline. It is neither a kitty for last-minute whims nor a mattress to be opened the first time a lot slightly overruns. It is a technical reserve, justified by the nature of old buildings.

The invisible hazards of old buildings

Three families of hazards explain most of the drift seen in old properties.

Hidden services, first. Electrics, water supplies, drainage: in an old building they run inside walls, floors and false ceilings, often for decades, sometimes in materials no longer in use. As long as the wall is closed, everything seems fine; the moment it is opened, the picture changes. A circuit buried under plaster, a drain connected any old how behind a cupboard: discoveries that only appear once the works begin.

Wall linings and light partitions, next. Fitted over successive waves of previous works, they sometimes conceal disorders: trapped damp, attacked timber, cracked masonry, abandoned ducts. Redoing them costs more than dressing them up, and that cost is invisible until they are dismantled.

Damp, finally. Rising through walls, slowly seeping around joinery or a terrace: it hides under the paint and reveals itself as soon as you heat, insulate or close the home up. A property left vacant gladly delivers this kind of surprise, precisely when a new owner launches a renovation. Before demolition, some period materials also call for regulatory checks, which translate into precautions and sometimes extra steps.

These hazards justify the contingency. From abroad, you cannot pop in to look behind the cupboard or under the floorboards: the contingency is your peace of mind. Our advice on running building works from abroad covers this remote organisation in depth.

Set the right contingency aside, then leave it alone

The contingency is fixed at the same time as the budget, not when the surprise arrives. You express it as a share of the total budget, you record it as a line of its own, and you mention it to the tradesmen: a craftsman who knows a reserve exists works differently from a team that believes the budget is locked.

Its rules of use come down to three:

it only funds a genuine surprise, discovered on site and documented with photos and in writing;
every draw on it is justified, dated and tied to the lot concerned;
whatever is left at handover stays yours: it is not a hidden budget to upgrade the finishes.

In exchange, never dip into it for a more ambitious choice of tiling or kitchen. The temptation is always there, and it is fatal: a contingency spent on extra comfort no longer exists on the day damp appears behind the lining.

Avignon, Provence

Phase the works to spread the financial effort

A budget is not built only in columns, it is built in time too. Phasing orders the campaigns of works by priority: safety first, with electrics and plumbing; comfort next, with heating, joinery and insulation; finishes last, which only make sense once the services are secure and the walls closed.

This sequence has three budget virtues. It spreads the effort: each phase is funded close to when it starts, rather than committing everything at once. It allows re-estimating: between two phases you know your building better, and you price the next steps with more accurate quotes. It protects: you never pay for finishes that a later phase of works might damage.

For a non-resident owner, phasing also simplifies logistics: access to the property, inspection visits, periods of occupation. Some expenses, finally, arrive from outside: when the co-ownership votes a façade redecoration, it joins your budget plan without waiting for your calendar. Far better to have anticipated it in the phasing.

Tracking commitments against the budget during the works

The budget lives during the works: every quote approved, every deposit paid, every invoice settled moves the lines. Keep a simple tracking table, lot by lot: initial quote approved, amounts committed, amounts paid, remaining to pay. Three habits keep it honest:

every extra goes through a signed document before execution, never through a word on the phone;
every payment is tied to a dated record: quote, works statement or invoice;
every gap between committed and budget is noted and decided: one lot is arbitrated to keep another on track.

This follow-up takes a regularity that distance makes harder: time differences, missed calls, photos that arrive late. If you cannot maintain it yourself, the works coordination of the Home Select concierge service carries this follow-up for you: it informs and coordinates, the tradesmen carry out the works, and you keep every decision.

A renovation budget is not a figure set at the outset, it is a thread you hold to the very end. Every old property has its hidden services, its damp patches, its mysterious wall linings.

What Home Select organises for your works budget

Works are costed before the purchase offer, not after: your Home Select property finder brings a contractor or a project manager to the second viewing, so that the price offered accounts for what remains to be done.

After the signing, we introduce the project manager or architect who runs the project in your place, and the concierge service that opens the door and photographs progress. Running the works, the quotes and the handover are theirs, under their responsibility: our role is that there is a single point of entry.

Frequently asked questions

How much contingency should I allow for an old-property renovation?

A share of the total budget, decided before the first quote and kept until the end of the works. How much depends on the age of the property, the known condition of the services and how much opening-up of walls and floors is planned. The key is to treat it as a lot in its own right, used only for a genuine surprise.

How do I stop the budget from drifting during the works?

By comparing, at every stage, the amounts committed with the initial quotes, and by putting every extra through a signed document before work starts. A gap spotted early can be corrected by arbitrating between lots; spotted late, it becomes an overrun you simply absorb.

Should everything be done in a single campaign of works?

Not necessarily. Phasing lets you deal with safety and services first, then comfort and finishes, while re-assessing the remaining budget between phases. It is often the calmest option for an owner living abroad.

Why break the budget down by lot rather than one global figure?

Which hidden hazards does a renovation in an old building hold?

Three families come back: hidden services, electrics, water and drainage running through walls and floors for decades; linings and light partitions, which sometimes hide damp, attacked timber or cracked masonry; and damp itself, which shows as soon as you heat or insulate. None can be seen before the walls are opened, hence the contingency set aside from the start.

What goes into each lot of a renovation budget?

Structural work, demolition, partitions, masonry repairs and openings; electrics, from the consumer unit to the lighting; plumbing, supply, drainage and sanitary fittings; heating and ventilation; finishes, paint, floors, joinery; and a contingency line, set in advance and not earmarked. Each lot has its typical hazard, watched line by line.

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