Is it worth converting an attic?

[Will Osteen]

BP, I bought my first single family home bought earlier this year for just under $80k. The upstairs attic has a fairly large living space with some sub floor laid. It would add roughly 600 sq ft to the home if finished (Currently at ~1050 sq ft). I looked into having a general contractor finish the space to add value to the property. I have two quotes from general contractors both at roughly under $14k all in for everything. Does it make sense to finish the upstairs to add value to the home? I was thinking I could afford it at $10k or less. But am hesitant about doing it in phases if it's not worth the pay off at $14k. 

Will refinancing it after the upstairs is refinished will allow me to pull the money back out?