Please read the first post carefully and post in the thread that reflects your issue best. Go in order from top to bottom if you see multiple of the symptoms. The top ones are more specialized as t...
Ideas
For those who has just experience this bug, this is an ongoing bug that is affecting many many players. Archived here:
[ARCHIVED] Houses/Lots disappear/Error 800 or 801 | EA Forums - 11264502
A temp solution is load from a non corrupted save and play from there. Then start saving your lots and families onto your personal gallery. Start a new game, then download from your gallery. I limit myself by playing with less rental residentials lots. Adding new DLC's will take more memory and therefore accelerate the lot corruption.