How many Bedrooms do I have? Studio Accessory Apartment

[Evan Markley]

This is my first post, apologies if I'm in the wrong forum.

I have a Single family home with an attached accessory apartment in Westchester County, NY.  The accessory apartment is about 500 Sq/ft with a bathroom, closet, kitchen, and open main area(Living/Bedroom), large enclosed/screened patio and separate entrance.  The rest of the house is my primary residence and includes 4 bedrooms and 2 baths.

When we purchased the home it was listed as 4 Bedroom 3 Bath(Including the apartment Bath), and at the bottom of the listing it said includes Legal rentable accessory apartment.  My question is, shouldn't it have been listed as 5 Bedroom 3 Bath?

Thanks in advance!