Duplex ownership info?

[Asma Lama]

Really looking for some inputs. I am a first time home buyer and am planning to put an offer for a duplex which has two units separated by a wall. Both are 2bed and 2bath and currently the other unit has tenant. When talking to seller, the seller mentioned that each units has its own ownership although both the unit is owned by the seller and won’t be selling it together. Both units are listed separately and will be sold/bought separately and each will have their own closing cost. Looking at the county website, both units are in a single lot so technically those units have not been separated right?