I'm sure the price will vary depending on where you live. I know someone in NJ (about 1 hour outside of NYC) that hired someone to finish their 1400 - 1500 sq. ft. basement for about $12k. This included stud walls, drywall, electrical, carpeting, drop ceiling, 4 interior hollow core doors with trim work, and paint. It is one large room with the furnace boxed in. This price did not include any plumbing, heating, or insulation.
I am currently finishing my own basement that is approx. 1000 sq. ft. I plan on spending about $3500 - $4000 doing everything myself except the baseboard heat. There is no plumbing except for the new baseboard zone.
I'm not sure if this helps but it can show you what the potential costs would be if you hired someone versus doing it yourself, if that is an option.
Most importantly, however, would be to get at least 3 quotes from reputable contractors detailing exactly what is and is not included. You can then make an educated decision.