How Do I Find Source Of Leak That Damaged My Condo

[Brad Warshaw]

I bought a condo at the auction that has water damage and mold in excess of 15k to repair. I called the management company and they blamed it on a recent leak from the 3rd floor, I am on the 1st. I saw the work order and it seemed like a small leak from the 3rd floor and not what damaged my unit. It also has mold so It is too recent to be the source of damage. How can I find the water source that damaged my apartment? Thx