QM2...first timer

I want to book the QM2 sailing from Southampton to NY in June (can't really plan far ahead given my line of work), but now after reading this board I'm getting nervous that I won't be able to book a HC cabin. I use a manual wheelchair and can walk short distances... has anyone stayed in a non-HC cabin w/ a wheelchair? My chair can fold but it's a real pain in the butt to fold it each time I want to enter and exit the room as it requires taking off a number of parts. Also, I require a shower chair or at least a bench, do they have extras that they can bring to the room for me? I've had this done in hotels when my request of a non-smoking HC room w/ 2 beds couldn't be accomodated...but I'm guessing the ship bathrooms are far smaller...would the chair even fit??? Also, are there HC rooms that have 2 single beds as opposed to a double bed?