The local sightseeing is almost free and the best part is that everything is accessible with a walk. If you want you can have fun doing boating at Gadisar Lake for 50-100 Inr on sharing basis. As the city is located around the fort, it is easy to reach on foot and does not have an entry charge.
The next day I went for a Desert Safari. I got an overnight package from Hostelavie at 1500 which included everything from traveling,meals,stay and camel ride in the Desert for a day. You can get this even cheaper if you are travelling during some other time of year. The next day was spent exploring the market and city after which I took the over night train to Delhi.
Train = 450 x 2=900
Hostel = 250
Meals 4 x 100 = 400
Safari = 1500
Boating = 50
Total Cost = 3100
The remaining 300 was spent on small things like snacks in the train and traveling in the city.