There are free themes too ;-) Premium / Commercial themes generally cost between $20 and $100. It depends on the theme, and who is selling it ;-) Good luck!
Well I think there are so many free themes that are really good ones, so why to buy a new with limited support of say 1-2 year
If you Running under budget you can install free theme, which is basic thing, colors and structure is stereotype and no advance functions and features. This is appropriate if you want to start blog. When it comes to build new unique word press theme you should make specification of your requirement. illustrate and document it in file. make references of different website you like to follow. Approx. price ranges are between 100-500$. Don't negotiate quality of work. This will help for future web promotion. Regards Jaimin
It is very from company to company and also county to country. Because now a day India will to all development work at cheap rate as compare to other countries.
i agree that the price may vary but there are a lot of free templates. take a look http://www.websitetemplates.bz/free_templates.html
Never buy something which you can get for free. If you can't find a free Wordpress theme you like, just post here what you are looking for and I will see if I can show you one that fits your needs. Or post here what your blog is about and I can suggest some themes that might fit your needs. All free.