Methodology

How every figure on Tregie is collected, sourced and dated, and what our numbers deliberately do not cover.

By Jamey WeberPublished Last checked

One record per country

Each country has a single structured record holding 22 figures across prices, buying costs, taxes, the purchase process, residency and letting. Every figure carries three things it cannot be separated from: the value, the source, and the month it was last checked. The written pages read from that record, which is why a number in a paragraph and the same number in a table can never drift apart.

The editorial rule that follows from this is simple and absolute: no figure appears in the prose that is not in the record. If you find a number on this site with no source behind it, it is a bug.

Which sources we prefer

In order: the legislation itself, then the national authority that administers it, then a statistical body, then a professional firm summarising it, then a market index. So the Spanish transfer tax cites the regional rules and the Land Registry, the Greek golden visa cites Law 5100/2024 and Law 5275/2026, and the cost of living cites Eurostat.

Prices are the weakest category on any site of this kind, ours included. Asking-price indices from portals such as idealista and Spitogatos are timely but measure what sellers hope for, not what buyers pay. Official transaction indices are accurate but lag by months. We use asking-price data for the per-square-metre figures and official indices for the five-year trend, and the source line on every row says which is which.

What the ranges mean

Most cost figures are ranges rather than single numbers, because the honest answer varies by region, by property type or by buyer profile. Spanish transfer tax genuinely is 6 to 10 percent depending on the autonomous community. Where a range exists we show both ends rather than an average, and the calculator computes both ends too.

Total buying-cost ranges are the sum of the transfer tax, notary, registration and legal ranges in that country's record, rounded to something a person would actually quote. They assume a resale property bought by a private individual with independent legal representation. New builds are taxed differently everywhere and are called out separately on each country page.

What we deliberately do not cover

Agent commission, because in these markets the seller pays it and including it would overstate what the buyer spends. Mortgage arrangement fees, valuations and life insurance required by a lender, because they depend on the lender rather than the country. Currency conversion costs. Renovation. Furniture. Anything that depends on the individual property rather than the jurisdiction.

We also do not rate countries on lifestyle, weather, healthcare or safety. Those judgements are real but they are not measurable in the way a transfer tax is, and mixing them into a ranking is how comparison sites end up producing numbers that mean nothing.

Dates and updates

The date beside each figure is the month that figure was verified against its source, not the date the site was rebuilt. The last-checked date at the top of each page is the most recent verification anywhere in that country's record. If nothing has been rechecked, no date moves, even if the page is republished for an unrelated reason.

Full records are reviewed at least twice a year. Residency thresholds, transfer tax rates and short-term letting rules are checked whenever we learn of a change, because those three categories are where the law in these countries actually moves.

Corrections and reuse

Errors get fixed and the check date moves with the fix; we do not quietly amend a figure and leave an old date in place. If you want to cite a table from this site, the figures are published as structured data on each page along with their sources. Tell us at the contact page if something is wrong.