I have the Italian version of the game.

On the sheet of Sister Mary it is explicitly written that she starts with $0 (zero dollars). It seems a bit odd to me ...

Is it ok or is it a misprint ?

Nope, $0 is correct. If you look around, there is a thread about Sister Mary, which also lists (IIRC) the prices the investigator's starting + random stuff costs, all having a total of $25. Blessing for example is priced at $10 out of that 25.