What would the price of nokia lumia 520 be in october?

I'm currently using the Galaxy S4 but it has a lot of problems so I'm going to sell it off and save up for the iPhone 5S or the next generation of the HTC One. Here's the thing - the iPhone would be way too expensive when it comes out and it'll take about a month or two for the prices to fall and also for it to be available everywhere else so I was thinking of getting the Lumia 520 and use it till January or December. How much would the price fall for this device? And is it worth getting for like two months?

Sister, why you again wanna waste money?
Sell your s4 on olx.com, I'm sure you can get rs 30000 easily, add some money and get htc one