Board Thread:Questions and Answers/@comment-24497123-20140202142912/@comment-1285528-20140202160733

There are no actual cheat codes that you can enter in MySims PC. To unlock Cassandra's blueprints, you must befriend her which is very tedious.

The only way to "cheat" in MySims PC, is to open the games files and edit the coding, however if done carelessly, can corrupt your entire save file.