The auction price is the number everyone quotes and it is rarely more than sixty per cent of what lands in your bank statement.
Start with the auction fee, then inland transport to the port, then the shipping itself. Roll-on roll-off is cheaper than a container and considerably more nerve-racking.
At the European end come duty, VAT, and the homologation process, which varies enormously by country. Germany is thorough and expensive. Czechia is cheaper and slower.
Then there is the part nobody warns you about: the first service. Every imported car I have bought has needed something within the first thousand kilometres, and Japanese-market parts are not always on the shelf here.
Budget forty per cent on top of the hammer price and you will be roughly right. Budget twenty and you will be selling something to cover it.