Yes, in substance it is — and it is also legal and extremely common in Spain. Marbella agencies routinely share listings and split the fee between the agency holding the mandate and the agency introducing the buyer, so the same firm can end up on both sides of a transaction. The structural issue is not the sharing, it is the negotiation: one adviser cannot argue for the highest price and the lowest price at the same time. The practical test has two parts. First, who pays the fee, and out of whose proceeds — in Spain that is almost always the seller, which tells you whose mandate the agency actually holds. Second, is the dual role disclosed in writing before you make an offer? An agency that discloses it and steps back from advising on price is managing the conflict; one that does not disclose it is not.
Why dual representation is the norm in Spain
Spain has no single MLS in the American sense, but Marbella has several sharing networks through which agencies circulate each other's mandates. A buyer walking into any agency is therefore often shown properties mandated to other firms, with the fee split between the two. This is genuinely useful: it is why a buyer can see most of the available market through one contact rather than visiting fifteen offices.
The fee in Spain is paid by the seller, customarily around 5% and often higher on prime property, and it is paid out of the sale proceeds. That single fact settles the question of whose agent the agency is by default. It does not make the agency dishonest — most behave properly — but it does mean that the incentive, on the specific question of price, runs one way.
Where the conflict actually bites
Not on access, and not on paperwork. It bites at exactly three moments. When you ask what to offer: an adviser paid a percentage of the sale price by the other side is not a neutral source on that question. When something is found during due diligence: a defect, a licence issue, an unpermitted extension — the incentive to make it sound manageable is real. And when a second buyer appears: whose interest does the adviser serve in orchestrating a competitive situation?
The answer is not to refuse dual agency, which would cut a buyer off from most of the Marbella market. It is to know which hat the person in front of you is wearing at each of those three moments, and to take price advice from someone who is not paid by the other side.
What to ask, and what we do
Three questions settle it. Who pays your fee on this transaction, and what percentage? Do you hold the mandate on this property, or is it shared from another agency? And will you put the answer in writing before I make an offer? Any adviser who hesitates on the third has answered all three.
Our own position is deliberately narrow: on a given transaction we act for one side, and we say which. On the buy side we hold a search mandate and represent the buyer, including against sellers we might otherwise work with. On the sell side we hold the sale mandate and defend the owner's price. The two do not meet on the same property — which is the only version of this that survives a hard negotiation.
Sources
Primary and expert sources behind this answer:
- Colegio de Registradores — Spanish Land Registry statistics (Estadística Registral Inmobiliaria) ↗
- BOE — Ley de Propiedad Horizontal reform (community powers over tourist lets, April 2025) ↗
This page is general information, not legal or tax advice. Spanish property tax, residency and letting rules are complex, regional and change frequently; every figure and rule here must be confirmed with a Spanish abogado (lawyer), a fiscal adviser (asesor fiscal) or a notary for your specific situation before you act.
Sale mandates for private owners and developers — Marbella, Greece, Dubai, Mauritius, the Maldives and the French Alps. On any given transaction we act for one side, and we say which. Every rate and every fee on this page is sourced (official texts, land registries, tax authorities) and dated; pages are re-verified quarterly.
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