Skipping due diligence is how foreign buyers end up owning disputes instead of homes. The core checklist: a title search at the land registry confirming the seller actually owns what they are selling and how; a check for mortgages, liens, unpaid taxes, and other encumbrances that can transfer with the property; verification of building permits and that the structure matches what was approved, since illegal extensions become the buyer's problem; zoning and land-use confirmation; and for apartments, the building association's finances, rules, and any planned levies.
On the people side, hire a lawyer who represents only you, not one recommended by the seller or the agent, and use a licensed notary where the system requires one, understanding that in many countries the notary is neutral rather than your advocate.
Structure payments safely: deposits into escrow or a lawyer's client account, never cash to the seller, with contract conditions letting you exit if checks fail. For new builds, add developer solvency and completion guarantees to the list.