Cost to finish attic space?

[Anonymous]

We personally spent just under 18k to finish 600+ sq feet in our third floor about 8 yrs ago.
-already studded in
-already had the larger hvac needed
-needed electrical -hard wood floors including on stairs
-no skylights
-insulation
-ducting for the hvac
-new larger window, which was helpful to their third floor delivery of supplies/sheetrock
-attic ladders etc