Never kept rabbits but long time keeping guinea pigs
The removeable trays - there was a very sad post on here a while back that someone had a fox get into their small animal hutch via the tray . Foxes are clever and determined !
I had a wooden playhouse (belonged to my DC ) on a solid base . My DH adapted it , made two of the windows removeable but the space was infilled with bars , chicken wire and mesh ( predators/mice/flies) and bolts to secure back in.
We put a cement filled bucket in front of the door and a bolt./padlock
It had power points for light ( essential in the dark for feeding cleaning checking) fan and little heater .
I could stand up in it , so great for DD to sit with the pigs
As they dn't climb , I had hutches on the floor with cut out doors so they could get out to potter round inside the pig shed
I bought a 2nd hand rabbit hutch ( from a well known stre ) good scrub , disinfect , paint
It was attaxhed to the outside run for the first summer then we put it in the pighouse permentantly .
I have to say , I wouldn't have trusted it to keep my pigs safe 24/7 .
They were never left out unattended even with the hutch/run . Only when we were home .
Compared to rabbits ,guineas are much more fragile and very defenceless .
Look at some ideas for sheds for rabbits , if you are good with design you can store hay and paper bedding too .
My shed would've accomodated 12 according to the piggie guidelines , I had 5 at one time ( in a 2+3 group) which I think was full capacity .