The Costa del Sol has long attracted buyers from northern Europe, Scandinavia, Eastern Europe and further afield, drawn by the climate, the coastline and a property market that stretches from sea-view apartments in Marbella to golf villas around Sotogrande and new-build developments across Estepona and Mijas. The appeal is well founded. Yet the same small set of avoidable errors surfaces again and again in transactions involving overseas buyers, and each one can prove costly to unpick once contracts are signed. Most of these mistakes do not come from carelessness. They come from carrying assumptions formed in a different property market — a different legal tradition, a different tax structure, a…