There are several garages around. You can find them here. Street parking is metered and can be easily found, most of the time.
There’s some free 2-hr parking available on Gaskill and Lombard streets.
Note on Weekends, particularly Friday evenings and on a Saturdays, there may be some traffic and trouble finding street parking. Please plan accordingly.
Also, note that Philadelphia Parking Authority around here is pretty strict, so please pay attention (and the meter!).