Where to park a car safely in the Old Town of Warsaw?

My family is coming over from Belgium next weekend, by car. Question to the Warsaw-based PF? What are the options in Starówka to park a car in a guarded parking space?

I only go there by metro so I do not have a clue...
On the corner of Plac Zamkowy and Senatorska was such a place, but I do not know if it still functions....
I was thinking about the IBIS on the end of Bonifraterska - but would they accept non-residents parking there (for a fee).
There is also the underground parking lot at Plac Krasińskich - but that is not guarded of course.
Other options?

Yes - it's not for residents only.


It still exist.


As I see, it is marked as guarded now.

Check this map for all guarded parking lots in the area of Old Town in Warsaw:
mapa.targeo.pl/platny-parking-strzezony-calodobowy-ztp,miejsce_5303592