Sao Paolo isn't a cruise port, but is served by the port of Santos. Added up, Santos is the embarkation point for fifteen cruises anually from MSC to, as well as other places.
Overall Sao Paolo is rather affordable compared to other ports. Prices are around the same throughout the year. See the chart below for the monthly average cost per day (Cruises only depart from Sao Paolo between March and April).
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