I recently ended a rental agreement with an option to purchase with a person who prematurely filed an eviction suit in small claims on the 2nd day of the month when I had 5 days to pay rent. I counter-filed for my option to purchase deposit back due to the original contract I signed. We went to court and the judge, even though acknowledging the fact that the Landlord admitted to taking the contract, making changes and having both the rental agreement and option to purchase agreement changed and notarized after I signed, ruled in the Landlord's favor and ordered a judgement including my deposit and an additional $1,800 in damages. Isn't a contract considered void if changes were made and a notary was involved after executing?

When you got a copy of the "changed" agreement that is when you were suppose to challenge it, if you were aware of the changes but did not challenge it,

It is cosidered voidable, but not automatically void, and only those changes may be vioded at some point.

Also if you accepted the changes without challenging them, then it shows an acceptance of changes.