I've got a c&c cage for one of my buns. Its 2X7 with a 2X1 shelf, a 2X2 shelf and a 2X4 shelf. I've got no suport for the shelfs and don't need it. I just have zip ties on it. My rabbit in it is very small (1.33kg) but my cats (which are huge i.e they need to loose weight
) were in the cage and it suported them. I think just to be prepared you may need suport but if you use lots of zipties and for a lionhead you may not.
I am changing my cage as I'm going to bond all three of my buns after they recover from there neutering.
Another idea instead of NIC cage is a dog crate with a pen outside.
Or just an Xpen.
I know my lionhead can jump two nic grids. So a top or higher should be fine.
Though I will say to bunny proof whatever room the cage will be in now. So if they do get out then there safe.
Im not sure if anyone mentioned to get a good vet pior to getting the bun. A rabbit savy vet is a must. Also if your rabbit won't be neutered/spayed then make sure you have money to do it when the time comes. Also see if theres any vaccines there that they give rabbits (i know here we vaccinate against VHD and myxo)
Oh and a carrier to bring to the get too.
Also this is a lil offtopic but wherever you are getting your rabbit, maybe ask for something familiar to the rabbit like his foodbowl/waterbottle/fav toy etc. It may help him settle in a bit not having EVERYTHING new!