Hello saurabh82,
To start of, always remember GOOGLE if your Best Friend,. Use it, you will find answer to these types of questions faster and more accurate. But since you have already asked the question here, i will try my best to provide my knowledge.
Now, I dont really know what the price per watt,etc is in india so I cant really say how much power your pc will take, but if you are worried about electricity bill then don't worry. I use a high powered gaming pc (with 700 watt psu) almost 15-20hrs every day and the max bill i got for a given month was Rs.2,300 (including my AC which I keep ON for 18+ hrs a day), so I dont think your pc with much lower PSU will consume anymore than 600-1000Rs per month (considering you run for pc 27/7.
Moving On, for VPS , if running your computer 24/7 is resulting into a PROFITABLE Business for you , then I do suggest you get a VPS (thou remember it will consume more power - for charging its battery).
Lastly, You can run your PC 24/7/365 days without even shutting it down for once, provided you have an adequate cooling solution for your CPU or your room temps a very low (keep the CPU and Motherboard Cool and you can run your PC indefinitely until it expires).
I hope i cleared some things up for you.
-DS