Installing washing machine worth it

Hi all, 

I have 4 family units in Irvington, and I live in 1 unit. There is a laundry machine in the basement ( 2 washers, 2 dryers). I wonder if adding an in-unit machine will improve value or be worth it in terms of appreciation.

The building has a simple layout. Is 4 units on 2 floors. The first floor has 2 units and the second two. From the outside, it looks like 2- 2 story family weld together. They have the same layout, and there is a closet in the corridor. Those closets align perfectly, and I want to use them for the washing machine.

Doing so will free the basement, and I can clean it. Not sure what I will do with it so far. Each tenant will have to agree to a fee if they want to use the hook ( for example, $100 ), and if I install the washing machine, that goes to ($150-200) per month. Those are just examples. Otherwise, the hook will just stay empty.

So my main question is: will this bring me back value? I don't want to spend, and the appraisal comes back the same.

A plumber asked me $8000 ( material included for the installation ). All the plumbing, the exhaust installation ( will go through the roof ). 

But that does not cover electrical and general construction (fixing the drywall and this kind of stuff ).

Your advice, please.