The ZTL is the restricted traffic area that’s forbidden between 7AM and 8PM and is reserved exclusively to residents of the historic center of Bologna. However the apartment is located near but outside of it, so you can reach it with your car without getting fines. Just pay attention to not pass accidentally under a ZTL camera
You can recognize the ZTL by this sign:
Beware of lines on the ground: the white lines are exclusively reserved for residents, you must park into the blue lines.
On-street parking costs € 1.80 per hour from 8am to 8pm. Before 8am and after 8pm it is free.