Responsive Template

Hi,
How much will it take to turn e ready-made template into responsive one ?? I have to make one responsive but need to know the pricing. If it's around my budget, I need it earlier. I had no problem before but when I today saw my site with a Android Device running on Jelly Bean and 4.5 qHD Screen, I got shocked ! So, I need it. If the cost is much higher, than I ownself will try.