As I visited last week to South Goa, I had 10000 per head for 2 days which includes travel, watersports, food Expenses. If you wish to visit dry places, you can try below
LIGHT HOUSE BETUL you can experience mesmerizing view.(Check out my profile for South Goa photo and video)
KABO DE RAMA
THE THREE KINGS CHAPS If you like to experience watersports below are the information. Watersports combo costs 2000 which includes, Parasailing, Jetsky, Ringo And Banana Ride. if you go to Palolem Beaches for Boat Ride it will cost 500 per head, 20mins ride to few beautiful beaches like Butterfly beach and Honeymoon Island also they will show you monkey forest and turtle rock all this will be covered in 45mins which is worth for 500Rs. they will allow you to play in Honeymoon Island for 15-20mins however when I played water was dirty full of plastic and tree figs and logs. we also got allergy for playing in such water. also if you choose to take Dolphin ride at Vasco da Gama,it will cost you 1500 per head, Which includes Scuba Ride and You can see Dolphins and have unlimited drinks. you cannot cover all this in 1 day, you need atleast 2 days.
South Goa is too beautiful and u would require a minimum of 2 days to explore main places. These include - Palolem beach, Butterfly Beach, Cabo de Rama, Cola lagoon, a lot of these info is on my Goa posts on insta @crazy_indian_nomad