Was able to remove mainline clog via roof access. Followed with camera inspection and found several issues. 1. There is a root intrusion in sewer main where sewer exits the units causing clogs 2. There is what appears to be an old cable snake blade stuck in the sewer line 3. There is what existing cast iron drain has large amounts of scale and build up in the line leading to clogs Recommend digging up and performing repair on root intrusion behind units 18 D and 18E. While performing repair we can install a mainline clesnout and perform descaling and hydrojetting to clean up existing cast iron drains as well as remove the snake blade