Can I finish a basement that isnt the proper ceiling height?

[Chike O.]

Hello folks,

I am currently in the process of finishing my first rehab. The house is a 2 story 3/1.5 single family with a basement. Due to a lack of space on the 2nd floor, there was not adequate space to add a 2nd bathroom so that I could have a master suite. Nor is there space on main floor to add a shower to the half bath. Well actually there is, but due to delays with finding a contractor that was reliable and "affordable", alot of time was lost so reconfiguring is just not feasible, especially since I am pretty far along in the rehab all things considered. 

So, my idea was to add a shower to the half bath in the unfinished basement, but not finish the basement. My idea was to flat black the ceiling and paint the walls and floor to clean it up and make it look decent. 

My agent is telling that I will not be able to get what I planned on due to recent comps, (there are only a couple recent comps) due to no finished basement, lack of a 2nd full bath, etc.

My reasoning for not finishing the basement is due to time/money as I have hard money and have had the property for 6 months, and then due to the fact that the basement height is 6'8 in one are to 7', which I know for habitable space should be 7' at least. 

Could I still just finish the basement so that buyers see a "finished" basement, even if the height is not tall enough and the sqft cant not be counted as part of the house? 

Does my idea of adding a full bath to a unfinished basement make sense or will that add zero value since its in the basement? I felt like 1 full bath in a house is not enough. 

Any advice would be appreciated.

Thank you