There is really no easy way to give you an idea of the value without knowing the specific location. In the past three months in UA, homes with rec rooms in the basement have sold for anywhere between $120/sq ft to $244/sq. ft Homes without a finished basement sold between $108/sq/ ft and $217/sq. ft
If you would like to provide a neighborhood or specific location, I would be happy to give you detailed info.
Do your Lower Level/Basement have an ingress/egress window(s) ? Does the basement have a sliding glass exit to the outside? Do you have a finished bedroom and bathroom in the basment? Is your Lower Level professionally finished with drywalled walls and ceilings or do you have a drop down ceiling and painted brick/cement walls? Is the cement floor merely painted or do you have a laminent or carpet covered floor?
Tle Columbus Mutliple Listing Service now also allows Realtors the opportunity to add additional finished square footage in a professional finished Lower Level.
I'm going to slightly disagree with my friend Tristam. While I agree that you will not get 100% of your money back on a finished basement in 43221 (or anywhere else) I do believe that having a professionally finished basement will add value to your home. That has been my experience and I've been doing this a while. Now, will you get 100% return? No but you will get some realized value for a finished basement. Indeed, it is hard to gauge it, but depending on how it's done and how much it costs you might get anywhere from 10-50% back on your investment. I've seen some bring even more. The % that you get back depends on several factors, too many to mention. But I do agree with Tristam, don't do it if you're just trying to sell your home.
If you are going to finish your basement, do not ever skimp on lighting. ALWAYS put in recessed lighting to make the room more bright, rather than hanging fixtures.
The other caveat of finishing your basement in UA is that the homes often get water in extremely heavy rain. Buyers and agents are looking hard for signs of water in every UA home. Buyers would sometimes rather see block in at least part of your UA basement, because it means they can gage if you have had any water intrusion.
I'm an agent and the two homes I have bought to live in, in UA, have both gotten water intrusion at some time. Both homes I have lived in UA are 43221, and the majority of my sales are here, so by default I know way too much about finishing basements in UA!
To make long story, short, you won't get your money back here for finishing your basement, so don't bother doing it, unless you are doing it for your own family's use :-)