Sabaudia is the strongest choice for a family buying a second home near Rome among these three towns, combining a protected natural park setting, long sandy beaches, and a well-established residential community that rewards year-round ownership. Its position within the Circeo National Park limits overdevelopment, preserving long-term lifestyle quality and property values in ways that more built-up coastlines cannot guarantee. Santa Marinella suits families wanting a quicker Rome connection but offers a notably smaller sandy beach area, while Anzio draws historically curious visitors rather than residential family buyers.