My crate is big enough for me to curl up in, and I'm 5'9", and 169 lbs.
I chose a crate this big because for starters, I didn't know how big Naja would be when fully grown, and also so that she has more then enough room to move around, change lying positions, and to snuggle with Moo.
I rarely ever crate her nowadays. Usually only when I'm working nights or whenever else she can't sleep with me. I still don't fully trust her in the house on her own though.
I think getting a crate is a good idea, crate training is relatively easy if you're consistant with it. Start off by only feeding and giving Buddy water in the crate. Give him Toys to chew on in his crate, and lots of yummy treats. I like to keep Naja's crate covered with a blanket so that it has more of a "den" like feel to it inside. I think the crate will save you quite a few noise complaints, and even more headaches due to barking. Naja is what you would call a Nuisance barker when left to her own devices at night. She will bark uninterrupted for what feels like
hours. Luckily we really don't have any neighbors, and I never leave her outside for more then 5 minutes at a time at night.
Oh I almost forgot to mention, I always keep a fan going trained on the crate when Naja is in there, it helps to keep her cool.