There is no single cheat code to unlock every lot in The Sims 2. However, these methods achieve the same result:
moveObjects on (Build Mode)Enter moveObjects on in the cheat console (Ctrl+Shift+C). In Build Mode, you can now place houses on any lot, including occupied or “unbuyable” ones, effectively bypassing the lock.
Install via Documents\EA Games\The Sims 2\Downloads\. Always backup Neighborhoods folder first.
Edit Neighborhood.iff in SimPE to flip lot ownership flags. High risk of corruption; only for experienced modders.
Use moveObjects on for quick building access. Use a Lot Ownership mod for legitimate gameplay unlocking. Avoid raw file editing unless necessary.