Goa is really two different holidays wearing the same name. North Goa - Baga, Calangute, Anjuna, Vagator - is where the beach shacks, nightlife, water sports and flea markets are, built for groups and short, high-energy trips. South Goa - Palolem, Agonda, Colva - trades that energy for quieter beaches, upscale resorts and noticeably fewer crowds, usually at a higher price point for the same star rating.
The other detail that trips up first-time visitors is the shutdown season: most beach shacks, water sports operators and a fair number of budget stays close down for the monsoon between roughly June and September, when the sea is too rough for swimming anyway. Outside that window, November to February is peak season with the best weather and the highest prices, while March-May is hotter but noticeably cheaper.
Since "Goa package" can mean a nightlife-heavy North Goa weekend or a quiet South Goa resort stay, always check which half of Goa an operator's itinerary is actually built around before comparing price.