Seven factors explain most of the cost of a renovation: scope (how many rooms and how deep), the condition of the services, the materials chosen, the amount of strip-out and debris, access to the property, whether it is occupied during the works, and the timing. Location, paperwork and the owners’ community add further variables. None of these can be reduced to a price per square metre, but each can be seen in an itemised quote.
How does scope affect the cost?
Scope has two dimensions: breadth and depth. Breadth is how many rooms are involved. Depth is how far down the work goes in each one — a cosmetic refresh (paint, fittings), a surface renovation (new floors and tiles on existing services), or a deep renovation (services, partitions, layout).
Depth matters more than breadth. Repainting a whole flat may cost less than renewing one bathroom down to the pipes. When you describe your project, try to say for each room how deep you want to go. It is the single most useful piece of information for a first assessment. See full renovation cost for how scope plays out across a whole property.
Why does the condition of the services matter so much?
Plumbing and wiring are hidden, spread through the whole property and connected to everything else. If they are recent and sound, they can stay and the quote focuses on finishes. If they are original in an older building, they usually need renewing, and that brings chasing, making good and coordination with every other trade.
This is the factor that most often separates two quotes for “the same” job: one builder includes the services, the other assumes they are fine. Photos of the fuse board and the bathroom pipes help us judge it early. Read more on rewiring and plumbing cost.
How much do materials change the total?
Materials affect the supply lines directly and the labour lines indirectly. A tile can cost several times more than another of similar appearance, and large formats or complex patterns take longer to lay. Taps, sanitaryware, kitchen units and worktops have equally wide ranges.
The practical approach is to decide the level you want for each room before the quote, or to agree material allowances in the quote and adjust them once you choose. That way the labour lines are fixed and only the material lines move. We can buy materials as part of the job; if you prefer to supply some items, the quote changes to “fit only” for those lines.
Why do strip-out and debris deserve their own lines?
Everything that comes out has to be broken up, bagged or loaded, carried to a vehicle or skip and taken to an authorised facility. The volume depends on what is removed: tiles and screed are heavy; partitions are bulky; a full kitchen fills a skip quickly.
The way debris leaves the building is just as important. A ground-floor flat with a skip at the door is easy. A top-floor flat without a lift, or a street where a skip needs a permit, is not. A quote that does not mention debris is either including it somewhere unclear or leaving it to you. For larger strip-outs without renovation afterwards, our network site demolicioninteriormalaga.eu covers interior demolition.
How does access to the property change the quote?
Access covers everything between the street and the room: parking for delivery vans, the size of the lift, stairs, narrow corridors, gated developments with delivery hours, steep plots. Every material that goes in and every bag that comes out passes through that route.
Poor access does not make a job impossible; it makes it slower, and in renovation time is cost. Large items such as plasterboard sheets, long worktops or large-format tiles may need special handling. On villas, scaffolding or platforms for external work are part of access too. Tell us about access when you request a quote — it saves surprises on both sides.
Does it matter if someone lives in the property during the works?
Yes. In an empty property, rooms can be stripped in sequence, services cut when needed and dust controlled with fewer precautions. In an occupied home, work is done in smaller zones, water and power have to be kept running for the residents, furniture is moved and protected, and the site is cleaned at the end of each day.
The same applies to holiday rentals that are still being let between phases. Occupancy does not change what is built, but it changes how it is built, and that shows in the quote. The blog post on why quotes differ looks at how builders price it differently.
How does timing affect the price?
A flexible start and end date lets the work follow its natural sequence: one trade after another, materials ordered with normal lead times, curing and drying given the time they need. A fixed deadline — before the summer letting season, before a move-in date — may require trades to overlap, extra people on site or faster materials.
Season matters as well. External work is planned around weather, and some communities restrict noisy work during summer months. If your date is fixed, say so from the start; the quote should show how the schedule was planned to meet it. Our guide on adjusting a budget explains how phasing can help when time and money are both tight.
Which other factors can affect a quote?
- Paperwork: municipal fees and taxes, and a technician’s fees where the scope requires them. We flag them but do not process them.
- The owners’ community: rules on hours, lift protection and works affecting shared elements.
- Location: distance and parking in town centres or remote areas.
- VAT: the rate depends on the property’s use and AEAT conditions; see VAT and grants.
- Unknowns: hidden defects that cannot be seen on a visit.
Official sources
Bauman Raymond Attila · Presupuesto Reforma · Avenida Antonio Belón 3, Marbella. Last reviewed: 05/11/2026.
