The yield on the listing is not the yield you get

Every listing that mentions an investment case quotes the same number. Annual rent, divided by asking price. It is easy to compute, it is the same arithmetic everywhere, and it is almost never what you end up with.

That is not dishonest. Gross yield is a comparison tool, and a good one: it tells you a flat in one town is priced more aggressively against its rent than a flat in another. It is just not a return. Four things sit between it and your account.

The purchase costs are not part of the listing, but they are part of your investment. Transfer tax alone is several points of the price and varies by region, and notary, registry and gestoria sit on top. Compute the yield against what the flat actually cost you and it drops before you have collected a single month of rent.

That is the first correction and the easiest to forget, because the price is the number on the page and the costs arrive weeks later. What buying actually costs, region by region.

Community fees, IBI, insurance, and the repairs that are not optional. In an older building with a lift and a pool, the community fee alone can take a month of rent a year.

None of this is exotic. It is simply absent from a calculation that only knows two numbers.

Two people can buy the identical flat, let it for the identical rent, and keep materially different amounts, because what they pay turns on where they are tax resident and not on where the property is.

An EU or EEA landlord is taxed on the rent after deductible costs. A landlord resident outside, which since Brexit includes the UK, is taxed on the gross with no deductions at all. Same flat, same tenant, different bill. How the rental income rates work.

A flat between tenants earns nothing and still costs everything. So does a flat waiting three weeks for a repair. Nobody advertises a vacancy assumption, and a yield quoted on twelve months of rent quietly assumes there is never one.

There is a second sting for a second home rather than a let: Spain taxes an empty property on an imputed income anyway. Owning it and not letting it is not a neutral position.

Use gross yield for what it is good at. Two flats, same town, one at 6% and one at 4%: that gap is real and it tells you something about how each is priced.

Then stop. The moment you want to know what you would actually keep, the question stops being about the flat and starts being about you: your residency, your costs, your financing, how long it sits empty. That is arithmetic no listing can do, because the listing does not know any of it.

It is the whole reason Yald asks who you are before it shows you a number. Run the flat you are looking at.