Begin with the likely future buyer pool, not only personal preferences. Compare genuinely similar properties, visit outside summer and calculate total ownership costs.
Use an independent escribano to verify title and registered information. Involve an architect, agrimensor or other technical professional when plans, boundaries, construction or moisture risks require specialist review.
Confirm that additions are documented, budget realistically for work and avoid paying a large premium for highly personal features future buyers may not value. Most importantly, establish your price range and walk-away point before emotion takes control.