Last OV or what to expect from guarantee?

So I booked an OV for Aug 25th. They told me last OV room it was a handicapped room 5166. I was abit surprised they would let us stay in it as we don't need a handicap room. Now when you check it's guarantee OV. Im thinking what? Its shows no rooms available? Balcony was a few hundred dollars over choosing Fantanica category ☹. We are on a budget due to going on other trips.

If I request a guarantee I don't know what to expect?

Often times, those with guarantee bookings get a free upgrade - usually to the next category of cabin. YMMV. You keep the "Experience" you originally book e.g if you book a Bella OV you may get a Fantastica or even an Aurea balcony cabin but you will only get the Bella benefits.