Two properties priced in different currencies need one comparison basis

A method for comparing two property prices across currencies without letting different dates, reference rates or settlement costs distort the housing decision.

2026-09-14

This article reflects the named expert’s practical perspective. See NovAsia’s editorial policy for how material is prepared and reviewed.

A THB 3.5 million apartment and a USD 95,000 apartment cannot be ranked by looking at the two headline numbers. Before the buyer can say which is cheaper, one price has to be translated into a common reporting currency.

That sounds obvious. The mistakes usually enter through the details: one property is translated using Monday's rate, the other is discussed against Friday's budget, a public reference rate is treated as an executable deal, or conversion fees are quietly folded into one property's “price” but not the other's.

A clean comparison keeps those layers separate.

Pick the reporting currency before judging the homes

The reporting currency should be the one that makes the buyer's decision easiest to understand. It could be the currency of their savings, income or personal budget. It does not have to be the currency in which either property is legally priced.

Suppose, only for illustration, the buyer reports everything in USD and uses a hypothetical comparison rate of THB 35 to USD 1. The THB 3.5 million property becomes USD 100,000 on that basis. The second property remains USD 95,000.

We now have a USD 5,000 headline difference. We do not yet have a conclusion.

Use the same timestamp for both conversions

If the common basis is meant to compare the properties, it should describe the same point in time. Translating the Thai price using one day's reference and the dollar price against a home-currency budget from another day introduces an FX move into the property comparison.

A buyer reviewing the shortlist a week later can update the reporting basis. The important part is to update both secondary values together while keeping the original listing or contract currencies visible.

This makes changes understandable. If the converted THB property moves from USD 100,000 to USD 98,000 solely because of the chosen reference rate, the apartment has not automatically become cheaper in baht. The reporting view has changed.

Keep the original property price visible

I would never replace the original price with the converted figure. The original amount tells the buyer what the seller or contract is actually asking for. The converted amount is an analytical layer.

That distinction becomes important when the buyer shares a shortlist with someone else. “USD 100,000” can easily be mistaken for a dollar-denominated offer if the THB 3.5 million source price disappears. A dated label such as “comparison equivalent” is more honest.

It also helps when the seller changes the actual price. A new THB amount is a property event. A new USD equivalent caused by the FX basis is not the same event.

Treat a reference rate as a measuring tool

Official reference rates can provide a neutral and reproducible comparison basis. They are not promises that a large property conversion can be executed at that level. The ECB explicitly states that its reference rates are published for information and may not reflect actual transaction conditions.

That is exactly why I like them for the first comparison: they can be a ruler without pretending to be the final settlement quote.

When the buyer moves from comparing homes to arranging payment, the question changes. Now the relevant figures are provider terms, source amount, recipient amount, fees, validity and timing. A transaction quote can differ from the reference basis without making the property comparison wrong.

Put settlement costs beside the price, not inside it

Assume our common-basis comparison shows USD 100,000 versus USD 95,000. The first property may require a currency conversion while the buyer already holds dollars for the second. The real cash difference could therefore be more than USD 5,000.

I show that in a separate execution-cost line. Doing so preserves the ability to change the funding route without rewriting the price of the home itself.

The same principle applies to instalments. A THB property payable over several dates can be translated in full at today's common basis for shortlist purposes. That does not mean every future instalment has already acquired today's actual USD cost.

Re-run the currency layer before changing the property decision

A common basis is useful because it can be refreshed. If currency conditions change materially during the search, update both properties, then ask whether the new budget difference is large enough to affect the housing decision.

Sometimes it will. A property that was comfortably within the buyer's source-currency ceiling may no longer be. Sometimes it will not; the difference may be small compared with location, layout, readiness or the payment schedule.

The key is not to let FX noise impersonate property information. A common date and common reporting currency tell the buyer what part of the difference comes from the two homes and what part comes from the lens used to compare them.

Sources

• European Central Bank — “Euro foreign exchange reference rates” and ECB Data Portal “Exchange rates”: dated reference data are intended for information and may differ from actual transaction rates. Accessed 2026-10-06.
• Bank of Thailand — “Daily Foreign Exchange Rates”: an official source of dated Thai FX data, used here as an example of a comparison reference rather than an executable quote. Accessed 2026-10-06.